Quantitative Research Proposal
The Accuracy of Wet Mount compared to FemExam in Diagnosing Bacterial Vaginosis
Mick Carlson, CNM, MS
Institute of Midwifery, Women & Health, 2001
Philadelphia University, 2001
Bacterial vaginosis (BV) is the most common cause abnormal of vaginal discharge. It is a polymicrobial condition that is a result of the alteration in the vaginal flora. It is not typically sexually transmitted. It affects as many as 25% of women in the United States. As many as 50% of women with BV are asymptomatic. Several obstetrical complications have been linked to bacterial vaginosis. Among these are preterm birth, premature rupture of membranes (PROM), chorioamnionitis, postpartum endometritis, and post Cesarean section wound infection. Treatment of bacterial vaginosis in pregnant women has been shown to reduce the risk for preterm birth associated with this condition. Routine screening has not yet been excepted by many clinicians as cost effective. While it is possible that routine screening will become standard in the future, the current US Centers for Disease Control (CDC) recommends screening high-risk pregnant women only. High risk pregnant women, according to the CDC, include woman who previously delivered a preterm infant. The recommended time for screening is during the early portion of the second trimester of pregnancy.
The question remains what is the most accurate and cost effective method for diagnosing bacterial vaginosis. The diagnosis is complicated due to the polymicrobial nature of BV. The "gold standard" for clinical diagnosis is Amsel's criteria which meets three of the following four criteria: 1) thin homogenous discharge; 2) pH >4.5; 3) release of amine odor "fishy" with alkalinization of vaginal fluid; and 4) the presence of clue cells on normal saline wet mount. Several methods have been used in the past to detect BV including pap smears and vaginal cultures. Both of these can be expensive and take some time to obtain the results. The most common method used for diagnosis today is the wet mount alone or in conjunction with pH testing. Recently, another quicker device has been approved by the FDA for use in the evaluation of vaginal discharge called the FemExam. It is a card impregnated with two indicators - one for pH >4.7 and one for the presence of amines >0.5 mM in the vaginal fluid. In order to use the card, a sample of vaginal secretions is placed directly on both of the indicators with a cotton tipped swab. If the pH >4.7, the pH side forms a plus sign. Similarly, if the amine concentration is >0.5mM, then the amine side forms a plus sign. This study will compare the accuracy of wet mount compared to the FemExam in diagnosing bacterial vaginosis.
Chapter One: Introduction to the Problem
Preterm birth and low birth weight remain the most important causes of perinatal mortality and morbidity in North America and Europe (Muller, et al, 1999). According to World Health Organization, low birth weight characterizes an infant who weighs <2,500g at birth, and preterm characterizes a birth that occurs at a gestational age of <37 weeks. A number of studies have demonstrated an association between bacterial vaginosis, a polymicrobial vaginal infection affecting approximately 25% of all pregnant women, and adverse pregnancy outcomes, including preterm labor, preterm birth, PROM, chorioamnionitis, and low-birth-weight infants (Hammill, 1999, McGregor, et al., 2000, Muller et al., 1999).
For most lower risk women, there are generally two different strategies for testing for BV: 1) Diagnose and treat any pregnant woman for BV who has symptoms of abnormal vaginal discharge, odor or vulvar irritation. 2) Routinely screen after 16 weeks pregnancy for BV, and treat and follow-up those with BV to make sure recurrences are minimized (Jelovsek, 2000). Routine screening has not yet been accepted by many clinicians, as many questions remain regarding risk/benefits ratio, use of clinical time and cost effectiveness.
Signs and symptoms of BV include unpleasant vaginal odor, often described as "fishy", discharge with a consistency of yogurt, and vulvar itching and irritation or both (Benrubi, 1999). Although signs and symptoms of BV may appear straightforward, they are unreliable in diagnosing bacteria vaginosis and must be differentiated from other causes of vaginal discomfort and discharge. Symptoms of BV often overlap with symptoms of candidal vaginitis, trichomoniasis, and atrophic vaginitis (Benrubi, 1999). In addition, BV may be asymptomatic in up to 50% of women with the condition (Benrubi, 1999). The "gold standard" for diagnosing BV is Amsel's criteria (McGregor,et al., 2000). Clinical diagnosis is based on the presence of three of the four clinical criteria. 1) Homogeneous, thin vaginal fluid that adheres to the vaginal walls; 2) Vaginal fluid pH >4.5; 3) release of amines odor with alkalinization of vaginal fluid, the "whiff test"; 4) Presence of vaginal epithelial cells with borders obscured with adherent, small bacteria called "clue" cells.
A misdiagnosis of BV frequently leads to repeat office visits and inappropriate or delay of treatment. The "gold standard" for diagnosing BV is influenced by subjective interpretation, but the criteria are all objectively based and meeting the criteria depends upon the clinician's olfactory sense or the interpretation of color changes on the pH test strips or assessment of the patient's complaints. Inaccurately performed wet-mount tests can lead to misdiagnosis. An accurate reading depends upon the quality of the microscope, the adequacy of the specimen and the skill of the observer.
Recently a simple and objective test has been developed that is FDA approved. It is the FemExam TestCard (Matria, 2000). This disposable card indicates the presence or absence of bacterial vaginosis. It is a card that has two indicators: one for pH >4.7 and one for the presence of amines >0.5 mM in the vaginal fluid. The FemExam tests are performed by collecting vaginal fluid with a cotton swab and wiping it across the colorimetric reagent sections of the card. The results are immediate. It is a "yes" or "no" device with simple plus (+) and minus (-) signs to signal positive or negative results. This test is convenient, odorless, and needs no color interpretation.
Significance to Midwifery/Women's Health
Significance of diagnosing and treating bacterial vaginosis during pregnancy is well documented. Midwifery care focuses on the normalcy and wellness of women's health care with a focus on preventative care. Midwives perform interventions that demonstrate a clear benefit to the women they serve. Nurse-midwives participate in developing and improving the care of women through documented research. Beneficial diagnostic procedures that are accurate, cost-effective, and that protect the individuals privacy should be implemented by the nurse-midwife. Which, then, is the best method for diagnosing bacterial vaginosis?
This study will explore selected outcomes of diagnosing bacterial vaginosis using the FemExam card compared to the wet mount method. This knowledge will assist midwives in making evidence-based clinical decisions regarding which method to employ when diagnosing bacterial vaginosis. The midwife can then effectively incorporate the best diagnostic tool to utilize while considering safety, satisfaction, accuracy, and cost when treating bacterial vaginosis.
The purpose of this research is to determine which method of diagnosing BV is more accurate, the wet mount or the FemExam. This research will take into consideration patient satisfaction, economical impact, cost of screening, and the simplicity of testing.
Type of Study
This quantitative research study proposal will be designed to collect data in order to identify the better screening/diagnostic test for the identification of bacterial vaginosis. Vaginal fluids will be collected from a convenience sample of pregnant women. The fluid samples will be tested for bacterial vaginosis using both the wet prep and FemExam methods for diagnosis. A descriptive correlational design will be used since the purpose of this study is to examine and describe the relationship of diagnostic accuracy of the wet mount compared to FemExam.
1. How does the diagnosis obtained through FemExam compare with the diagnosis obtained through Amsel's criteria in diagnosing bacterial vaginosis?
Theoretical / Operational Definition of Terms
Conceptual definition: Correctness precision ; true; in exact conformity with a standard.
Operational definition: Measured in terms of two indices: sensitivity and specificity. Sensitivity refers to the proportion of persons with a condition who test "positive" when screened. A test with poor sensitivity will miss cases and produce larger number of false-negative results. Specificity refers to the proportion of persons without the condition who correctly test "negative" when screened. A test with poor specificity will result in healthy persons being told they have the condition.
Conceptual definition: A device that has been approved by the FDA for use in the evaluation of vaginal discharge.
Operational definition: A testcard that has two indicators - one for pH >4.7 and one for the presence of amines >0.5 mM in the vaginal fluid. In order to use the card, a vaginal swab is placed directly on both of the indicators. If the pH >4.7, the pH side forms a plus sign. Similarly, if the amine concentration is >0.5mM, then the amine side forms a plus sign. FemExam is a simple "yes" or "no" device. This is a nominal-level of measurement.
Conceptual definition: the standardized criteria, "gold standard", (Mcgregor, et al., 2000) for diagnosing bacterial vaginosis. This is operationalized as Amsel's criteria is recorded in the patients chart.
Operational definition: Amsel's criteria is an example of nominal-scale measurement since clinical diagnosis is based on the presence of three of the four criteria. 1.) Homogeneous, thin vaginal fluid that adheres to the vaginal walls; 2.) Vaginal fluid pH>4.5; 3.) Release of amines odor with alkalinization of vaginal fluid, The "whiff test"; 4.) Presence of vaginal epithelial cells with borders obscured with adherent, small bacteria called "clue cells".
The proposed study will examine the accuracy of FemExam with the accuracy of Amsel's criteria in diagnosing bacterial vaginosis. As mentioned previously, inaccurately performed wet-mount tests can lead to misdiagnosis. An accurate reading depends upon the quality of the microscope, the adequacy of the specimen and the skill of the observer. Part of meeting Amsel's criteria, the "whiff test", depends upon the clinician's olfactory sense. The interpretation of color changes on the pH test strips can be difficult to distinguish acid from base if the pH is close to 4.5. There will be several data collectors and interpreters with some individual variations despite attempts to test for interrater reliability.
Chapter Two: Literature Review & Conceptual Framework
This literature review was conducted both electronically and manually. Full text articles were obtained from Southview Hospital and Wright State University Libraries. The internet based search utilized Proquest, Medline, and Web MD. The following subject headings were searched: Bacterial Vaginosis--definition, signs and symptoms, diagnosis, and complications related to bacterial vaginosis. Microscopy, Wet Mount, FemExam, and Preterm Labor were also searched. In addition to periodic literature, standard medical texts were used. Additional information was obtained from Matria by contacting their sales representative.
Bacterial vaginosis is a polymicrobial syndrome that results in a shift in the vaginal ecosystem, leading to a decrease in the normally predominant lactobacilli and an increase in anaerobes (Benrubi, 1999). No single bacterial organism is responsible for the condition, hence the name, "bacterial vaginosis." The cause of this condition is not fully understood but it is known to effect approximately 25% of women in the United States (Matria, 2000).
Bacterial vaginosis cannot be accurately diagnosed on symptoms alone since there are several vaginal conditions that share some of the same symptomatology and additionally, 50% of women with this disorder are asymptomatic. . The common symptoms of bacterial vaginosis and other vaginal disorders include: unpleasant vaginal odor, abnormal vaginal discharge, vulvar itching, irritation, or a combination or all of these symptoms (Benrubi, 1999). These common symptoms have a broad range of possible etiologies. Vulvovaginal candidiasis, bacterial vaginosis, and trichomoniasis are often misdiagnosed when the diagnosis is based soley on symptoms without any further physical screening or diagnostic testing. There are reports that up to 50% of women diagnosed with vulvovaginal candidiasis, based on clinical impression, actually have some other condition (Allen-Davis, 1998). This fact is important as health care, with its time constraints, is moving toward phone-based management and over-the-counter medications.
A study was conducted to see if nurses could arrive at an accurate diagnosis solely on the basis of telephone conversation regarding vaginal symptoms (Allen-Davis, 1998). Nurses from Denver-area Kaiser Permanente facilities were provided with standard intake history, which they employed when a patient called with vulvovaginal complaints. The nurses then diagnosed the condition and drew up a treatment plan, however they did not share this with the patient. The nurses invited every patient to visit either a nurse practitioner, a physician, a physician assistant, or a certified nurse midwife. When the patients came to the office, they were asked to complete the same standard intake history form. The women were then further evaluated by performing a routine physical examination along with measured vaginal pH, and specimens for vaginal culture. Following the evaluations, both the nurses and the providers were asked the question; "Based on what you know about this patient, is she someone you would have treated over the phone?" The results showed no correlation as to which women they would or would not have treated over the phone. Surprisingly, this study demonstrated that the nurses were more likely to treat patients over the phone than the physicians, nurse practitioners, nurse midwives, and physician assistants. An economical interpretation of these results may reflect that nurses can't bill for these services while practitioners can and do bill for these services.
This study appears slightly biased against nurses. The same standard intake history was used, and the same question was asked to both the nurse and the clinicians. The difference was that the nurses were evaluating the symptoms per phone conversation and the clinicians were evaluating the patients symptoms face-to-face and also conducting a physical exam before being asked the question; "Based on what you know about this patient, is she someone you would have treated over the phone?" It is much harder to be objective when asked this question after already physically evaluating this woman. Even so, this study is significant to show that health care, with its time constraints, is moving toward phone-based management. Given this reality, and demonstrated by the results of this study, bacterial vaginosis should not be a symptom-based diagnosis. A detailed history may be the first-line approach in evaluating vulvovaginal symptoms, but this must be followed up by further testing in order to make an accurate diagnosis.
Diagnostic Tests for Bacterial Vaginosis
The use of microscopy, pH measurements, and whiff amine tests on vaginal fluid is widely considered to be the standard practice for the evaluation of vaginitis (Wiesenfeld & Macio, 1999). A study was undertaken to see whether physicians use these office-based tests in the evaluation of women with vulvovaginal symptoms. This study took place at the Vaginitis Center at Magee-Womens Hospital, a referral based clinic for women with vulvovaginal disorders (Wiesenfeld & Macio, 1999). The data collected was obtained by reviewing medical records. Fifty different physician's medical records were reviewed for 150 office visits. The unselected cohort of women had come in for initial consultation and evaluation of vaginitis, sometime during 1995 through 1997. Interestingly, the charts reviewed showed that microscopy was used during only 63% of the visits and the measurement of pH and Whiff tests were performed even more infrequently- only 3% of the visits. A diagnosis was entered in 77 of the charts reviewed. Vaginal candidiasis was diagnosed in 61 visits, and bacterial vaginosis was diagnosed in 13 visits.
The results of this study indicate that most vulvovaginal disorders are diagnosed without implementing the "gold standard" of care. This suboptimal care can lead to misdiagnosis. The accuracy of diagnosis entered in this study is questionable due to the fact that bacterial vaginosis is much more common than vaginal candidiasis. One limitation to this study is that the data collected from medical records may not reflect the actual care provided. Inaccurate or incomplete documentation could be a factor. There may be several reasons why the evaluations for vaginitis are substandard. Some clinics and offices may not have working microscopes. With the implementation of managed care, time constraints may be a factor. The workup for vaginal complaints begins with a visual examination of the woman's discharge, followed by obtaining a sample of the vaginal fluid on a cotton swab. This swab is then used to test the pH. A wet mount for saline microscopic evaluation is then prepared. The seek and find for motile trichomonads or clue cells begins. Another slide with a drop of KOH and vaginal fluid is prepared to determine whether there is an amine odor. This workup includes many steps which could be a shortcoming and a reason why many physicians don't employ it. It is certainly time for clinicians to adopt optimal diagnostic protocols.
Amsel's clinical criteria is one diagnostic test for identifying bacterial vaginosis although there are several other methods that will be identified in this paper. The Papanicolaou smear, using a Gram-stain of a vaginal fluid sample, is another way to detect bacterial vaginosis. The Papanicolaou smear would be a convenient means of testing pregnant women since a Papanicolaou smear is generally performed at the initial prenatal visit.
A retrospective study was initiated at a community teaching hospital that was associated with a large multispecialty clinic (Green, 2000) . Medical records were reviewed for a 6-month period beginning September 1, 1997. Obstetrical patients who had been screened for bacterial vaginosis by means of the Amsel's criteria were identified. These patients also had a routine Papanicolaou smear performed at the same visit. Senior residents and faculty physicians supervised the Amsel's criteria for clinical diagnosis of bacterial vaginosis. The Papanicolaou smears were screened by cytotechnologists at the institution who were trained to recognize clue cells and abnormal vaginal flora. Identified were 159 pregnant women. Bacterial vaginosis, using Amsel's criteria was present in 45 of the 159 women. The Papanicolaou smear detected bacterial vaginosis in 30 women, including 22 of the 45 women with bacterial vaginosis diagnosed by the Amsel's criteria. Using the Amsel's criteria as a reference, the sensitivity and specificity of the Papanicolaou smear were 49% and 93% respectively.
This study clearly supports the Amsel's criteria as the best method to clinically diagnose bacterial vaginosis in the pregnant patient. The Papanicolaou smear method has a relatively low sensitivity for diagnosing bacterial vaginosis. The low sensitivity of the Papanicolaou smear might be explained by the fact that the Papanicolaou smear is taken from the cervix, while the wet-mount smear was taken from the vaginal sidewall. This could be relevant due to the fact that bacterial vaginosis is considered to be a lower genital tract infection.
The Affirm VP Microbial Identification test is yet another method for diagnosing bacterial vaginosis. This test is an "easy-to-use" probe that detects high concentrations of Gardnerella vaginalis. The commercial test system was used to detect vaginal pathogens from 176 consecutive women attending a sexually transmitted disease clinic for genital complaints. Vaginal swabs were used for culture of Gardnerella vaginalis and Trichomonas vaginalis, gram stain interpretation and wet mount evaluation. An additional swab was tested with the Affirm VP Identification test. Briselden et al (1994) reported accurate detection of 95 to 97 percent of women with clinical criteria for bacterial vaginosis using the Affirm VP Microbial Identification test. Specificity for this test ranged from 71 to 98 percent.
Using the Affirm VP Microbial Identification test may provide a less subjective test for bacterial vaginosis than other current methods. The pH paper is interpreted by comparing the paper with the color panel found on the package, which leaves room for over-or under-read pH. This probe could be a valid replacement for the wet mount. Although this probe is easy-to-use it has to be placed in an Affirm processor for 30 minutes before the results are available. This would mean calling patients with results which can be very time consuming.
Another more recent "easy-to-use" device has become available in detecting bacterial vaginosis. The FemExam (Hillier, 1998) was tested on 607 women. Sixty-nine percent of these women were symptomatic for infection, while almost one-half were negative for both pH and amine. Roughly 30% were positive for both elements, and about 25% were positive for one of the two elements. The researchers found that the FemExam Amines TestCard had a sensitivity of 87% and a specificity of 92% for detection of bacterial vaginosis by clinical signs (Amsel criteria). The positive predictive value was 79% and the negative predictive value was measured to be 95 percent. This credit card shaped TestCard has two simple indicators; one for pH>4.7, and one for the presence of amines >0.5mmol. A vaginal swab specimen is swabbed directly on the test element on the left and right sides of the card. Bacterial vaginosis is detected with a plus sign appearing on both sides of the card.
Unlike the pH paper, the FemExam does not depend on the interpretation of color changes in comparison to a color code panel. Unlike the whiff test, the FemExam once again depends less on subjective interpretation with the simple plus or minus sign appearing on the card. The FemExam TestCard provides a presumptive diagnosis for bacterial vaginosis since only two of the four criteria considered to be used for diagnosis (three of four Amsel criteria are required for diagnosis) of bacterial vaginosis. This card has been recently approved by the Food and Drug Administration for use in the evaluation for vaginal discharge. The results of this study support the use of the FemExam providing a point-of-care, presumptive diagnosis for bacterial vaginosis. The FemExam is less subjective then that of the Amsel's criteria. It is also easier to perform and interpret.
Risks associated with Bacterial Vaginosis
Why is it so important to diagnose bacterial vaginosis in pregnancy? Numerous studies have demonstrated an association between bacterial vaginosis and a range of adverse pregnancy outcomes, including preterm rupture of membranes, preterm labor, amniotic fluid infection, and delivery of low-birth-weight infants ( Hammill, 1999).
There are generally two different strategies for testing for BV during pregnancy: 1.) Diagnose and treat any pregnant woman for BV who has symptoms of vaginal discharge, odor, or vulvar irritation, and 2.) Routinely screen after 16 weeks of pregnancy for BV, and treat and follow-up those with BV to make sure recurrences are minimized (Jelovsek, 2000). Controversy exists for routine screening of all pregnant women for bacterial vaginosis. Many clinicians question the value of routine screening while considering the risk/benefit ratio, the use of clinical time, and cost effectiveness. Current recommendations call for bacterial vaginosis screening of high-risk pregnant women only; that is, those who have previously delivered a preterm infant (Hammill, 1999). According to the Centers for Disease Control (CDC), a test for bacterial vaginosis may be conducted early in the second trimester for asymptomatic patients who are at risk for preterm labor. Current evidence does not support universal testing for bacterial vaginosis (Centers for Disease Control and Prevention, 1998).
According to Pearson (1998), more research is needed to determine if it is best to target screening for women who have additional risk factors for preterm birth, or if routine screening for vaginal infections without symptoms should become part of prenatal care for women. Eschenbach (1998) reports a study indicating a probable cause-effect relationship between bacterial vaginosis and prematurity. Women with bacterial vaginosis were shown to have increased rates of both infectious agents and inflammatory cytokines in their amniotic fluid. They also had a higher rate of infection and inflammation of the chorioamnion. This is direct evidence that bacterial vaginosis causes amniotic fluid infection which leads to preterm delivery. It was also found that women with bacterial vaginosis have a 100-fold to 1,000-fold increased concentration of anaerobic bacteria in the vagina. This study gives one a better understanding of how bacteria in the lower genital tract can invade the cervix and travel into the chorioamnion and cause an amniotic fluid infection. Eschenbach recommends screening women at 15-20 weeks gestation those gravidas who: 1.) have a history of preterm labor, 2.) have a history of bacterial vaginosis, and 3.) have a very low preprenancy weight.
A study was conducted in Jakarta, Indonesia, to examine the association between preterm delivery and bacterial vaginosis in early and late pregnancy (Riduan et al, 1993). Women seeking prenatal care at three hospitals in Jakarta were invited to participate from December 1989 to December 1990. Evaluated were 490 pregnant women for bacterial vaginosis at 16 to 20 weeks and 28 to 32 weeks gestation. The researchers found that the risk of preterm delivery was almost doubled for women who had bacterial vaginosis in early pregnancy (16 to 20 wks.) compared to women who had bacterial vaginosis only in late pregnancy (28 to 32 wks.) The rates for premature delivery were 20.5% and 10.7% respectively.
This literature review revealed clear support for screening and treatment of bacterial vaginosis in the early portion of the second trimester of pregnancy. The major concept important to this inquiry is that only bacterial vaginosis diagnosed early in the second trimester of pregnancy plays a major role as a risk factor for preterm delivery. A diagnosis of BV at the time a woman presents with PROM or preterm labor may be of little value since irreversible damage may have already been done. It is difficult to know exactly how much preterm labor is thought to be caused or associated with BV since preterm labor is multifactorial. Approximately 40% of preterm births have an identifiable risk factor associated with the prematurity, such as, multiple gestation or previous preterm delivery. The other 60% are without an identifiable cause (Martius, et al, 1988). Study after study have linked BV with preterm labor. Also, treatment of BV during pregnancy has been shown to reduce the risk of preterm labor.
Another study was conducted to examine the prevalence of lower reproductive tract infections and to examine the effect of treatment in an effort to reduce risks of early pregnancy loss (<22 weeks), preterm premature rupture of membranes, and preterm birth (McGregor et al, 1995). This study began Jan. 7, 1991, and continued through March 31, 1992. Women initiating prenatal care at Denver General Hospital Obstetrical Clinic were enrolled in the program. This study was divided into two phases. Phase I (observational phase), women were examined at the initial prenatal visit and screened for bacterial vaginosis. They were followed up with reexaminations at 22 to 29 weeks and after 32 weeks gestation. Phase II (treatment phase), women during the second eight months of the study who were identified as being infected with bacterial vaginosis were treated with the recommended treatment regimen of the CDC (i.e. 300mg clindamycin po bid x 7 days). The overall presence of bacterial vaginosis was found to be 32.5 percent. This study demonstrated a significant reduced rate of premature rupture of membranes and preterm birth associated with the treatment of bacterial vaginosis. Clinical recognition and treatment of bacterial vaginosis appeared most effective in reducing the incidence of preterm birth, untreated preterm birth incidence was 21.8% where as treated incidence was 5.9%.
This literature review along with the previous review confirms support for the screening and treatment of bacterial vaginosis in an effort to decrease risks of preterm rupture of membranes, and preterm birth. One area of interest in this study is the criteria used to diagnose bacterial vaginosis. It seems a modified Amsel's criteria was used, identifying only two of the standard four criteria for diagnosis versus the "gold standard" of three out of four for a diagnosis. Strengths of this study would be that the same measures were used in diagnosing bacterial vaginosis and that both groups were evaluated by the same personnel in the same setting. The treatment used was standardized by using the CDC recommended regimen.
The economical advantage of any medical screening and treatment is always a consideration. What then is the economical benefit of screening and treating women with bacterial vaginosis? A clinical study was conducted in Germany (Muller et al, 1999) to estimate the economical impact of screening and treatment in comparison to no screening for, and no treatment of, bacterial vaginosis during early pregnancy. In three different gynecologic practices in Berlin, 300 consecutive pregnancies were studied. Patients were screened for bacterial vaginosis by identifying clue cells on a wet mount. The presence of clue cells is the single most reliable predictor of bacterial vaginosis (Sobel, 1997). Practice A treated the 63 (21%) positive cases of bacterial vaginosis with clindamycin 2% vaginal cream. Practice B treated the 62 (20.7%) positive cases with a lactobacillus preparation. Practice C did no screening. Total cost of delivery: Practice A-$493,159, Practice B-$497,619, and Practice C-$534,926. The net savings per delivery for Practice A, as compared to Practice C was $168. Costs applied to the clinical outcomes were determined from standard German references and the charges from university clinics. Factors that influenced the cost associated with bacterial vaginosis included the cost of preterm labor, preterm birth, low birth weight and other perinatal complications.
The estimated cost savings of screening and treating bacterial vaginosis is demonstrated by this study. If one were to apply this cost to the number of births at a specific institution they would have to multiplied by $168. For instance, a hospital conducting 1,000 live births per year, the total cost savings for screening and treating bacterial vaginosis would be $168,000; a significant savings. The limitation of this study is that the connection between bacterial vaginosis and preterm delivery was not completely demonstrated.
These previous literature reviews clearly support the fact that bacterial vaginosis is a most significant cause of prematurity. There are continued efforts being made to find the right test, the most accurate and affordable test, and a test that can be easily implemented by clinicians to identify genital tract infections in order to reduce the number of premature infants. What about a test that women themselves can perform? According to Saling (1998), women who participated in a "Prenatal Care Self-Examination" program checked their own vaginal pH twice a week. A study was conducted at one maternity department in the city of Eufurt, Germany. In Eufurt, 16 practitioners take care of the pregnant population. These practitioners motivated nearly one-half of their patients to participate in the "Prenatal Care Self-Examination" program. The women performed the pH test twice a week using a special glove which has an indicator on the index finger. After the introduction of the index finger about 2cm into the vagina, the women would compare the color of the test paper with the color scale included in the kit. If the pH was found to be abnormal, then the woman would contact her provider for further follow-up and treatment. The results of this study demonstrated participants less likely to deliver a premature infant and less likely to have premature rupture of membranes. The control group had a rate of 3.3% of deliveries <32 weeks, where as the participants rate of deliveries <32 weeks was 0.3%, a significant difference of 3%. The rate of premature rupture of membranes comparing the control group with the participants was also significantly decreased at 32.1% and 22.3% respectively.
With modern obstetrics emphasizing "prevention," this simple program, "Prenatal Care Self-Examination" sounds like a viable answer to a prophylactic screening test. The idea of the women being educated about genital tract infections and encouraging them to perform self-examinations is a positive step toward women taking responsibility for their own health and the health of their unborn. One negative feature to this type of testing is that it depends on the interpretation of color changes being somewhat subjective when comparing the index finger glove to a color code panel. The major concept to this inquiry is that it is a self administered test that has been shown to reduce preterm labor and premature rupture of membranes.
In conclusion, studies have demonstrated an association between bacterial vaginosis and preterm labor and birth. It is known that preterm labor and birth lead to unfavorable perinatal outcomes. There is a great economical impact associated with premature infants. It is also been demonstrated that treating bacterial vaginosis decreases the risks of PROM and preterm birth. It can be concluded that lives and costs are saved by treating this disorder. This study will be beneficial in identifying the most accurate and efficient method in diagnosing bacterial vaginosis.
A research study is guided by a theoretical/conceptual framework. "A framework is the abstract, logical structure of meaning that guides the development of the study and enables the researcher to link the findings to nursing's body of knowledge" (Burns and Groves, 1997, p.166). A theoretical framework to a researcher is somewhat like what a map is to a tourist. The map serves as a guide to your destination, and when conducting research, a theoretical framework serves as a guide or map to systematically identifying a logic, precisely defined relationship between variables" (LoBiondo-Wood and Haber, 1998, p.141).
Bacterial vaginosis is believed to represent a synergistic polymicrobial infection characterized by an overgrowth of bacteria normally found in the vagina. Lactobacilli, the dominant healthy vaginal bacteria, are replaced with anaerobic bacteria. Bacterial vaginosis is the most prevalent form of vaginal infection of reproductive age women in the United States. The incidence varies in patient populations. The reported incidences are as follows: 32%-64% in patients visiting sexually transmitted disease (STD) clinics; 12%-25% in other clinic populations; and 10%-26% in patients visiting obstetric clinics (Association of Professors of Gynecology and Obstetrics APGO, 1996).
Bacterial vaginosis has been found in 19-24% of pregnant, examined women in Germany, Sweden, Finland, and the United States (Muller, et al, 1999). A number of studies have recognized bacterial vaginosis as being directly related to preterm labor, preterm birth, PROM, choriamnionitis, and other suboptimal pregnancy outcomes (McGregor, et al., 2000, Muller et al., 1999). The costs in dollars of preterm labor, preterm delivery, the attendant low birth weight, and other perinatal complications due to bacteria vaginosis were nearly 41 billion in 1993 (Mueller et al., 1999).
The recent awareness of the risks related to bacterial vaginosis during pregnancy has lead to more attention to the screening and treating of women for bacterial vaginosis during pregnancy. Clinicians understand the value of prevention and the substantial reductions in neonatal morbidity and mortality related to premature birth. What makes a good screening test for bacterial vaginosis?
According to the Guide to Clinical Preventative Services, a screening test must satisfy two major requirements to be considered effective: 1.) Accuracy of the screening test and, 2.) Effectiveness of early detection. The purpose of this research will be focusing on the accuracy of screening for bacterial vaginosis. Accuracy is measured in terms of two indices: sensitivity and specificity. Sensitivity refers to the proportion of persons with a condition who test "positive" when screened. A test with poor sensitivity will miss cases and produce larger number of false-negative results. Specificity refers to the proportion of persons without the condition who correctly test "negative" when screened. A test with poor specificity will result in healthy persons being told they have the condition.
Key Concepts and Relationships
Method of diagnosing bacterial vaginosis (Wet Prep versus FemExam)
Wet Prep---------->Accuracy------->Better Screening/ Diagnostic test
FemExam---------->Accuracy------>Better Screening / Diagnostic test
This goal of this inquiry is to identify the better screening/diagnostic test for the identification of bacterial vaginosis. This study will compare the accuracy of the wet prep versus the FemExam with special consideration given to cost-effectivness. A more accurate screening test would improve the diagnosis of bacterial vaginosis allowing for treatment and better neonatal outcomes.
The purpose of this research is to determine how well the diagnosis of BV using the FemExam compares to the wet mount.
WM (ST) --------->A---------->DP
ST= Screening Tests
WM = Wet Mount for bacterial vaginosis
FE = FemExam for bacterial vaginosis
A = Accuracy
DP= Disease Prevention
Chapter Three: Methodology
This quantitative research proposal will be designed to collect data in order to identify the better screening/diagnostic test for the identification of bacterial vaginosis. This study will compare the accuracy of the wet prep versus the FemExam. A convenience sample of pregnant women initiating prenatal care during their 12th to 16th week gestation will be selected. The Centers for Disease Control, (1998) recommended time for screening is during the early portion of the second trimester of pregnancy. This convenience sample of pregnant women will be tested for bacterial vaginosis using both the wet prep and FemExam methods for diagnosis. A descriptive correlational design will be used since the purpose of this study is to examine and describe the relationships of wet mount compared to FemExam. Using this study the researcher will be able to compare positive and negative results for wet mount and FemExam and develop a hypothesis regarding the accuracy of the these tests. This research design is expressed in the notation:
I-----------Examination of Relationships---- l Interpretation of Meaning
I l l
I l l
FE-----------A--------------------------------------------- l l
Testing of Hypothesis
Internal & External Validity
Internal validity is the extent to which the effects detected in the study are a true reflection of reality, rather than being the result of the effects of extraneous variables (Burns & Grove, 1997).
External validity is concerned with the extent to which study findings can be generalized beyond the sample in the study (Burns & Grove, 1997).
Threats to internal and external validity and measures to control used in this study are:
1.) Inclusion and exclusion criteria for study subjects were designed to assure a sample population that would be receiving a pelvic examination on their first prenatal visit, limiting the investment demands on subjects in order to increase the participation.
2.) Subject questionnaire was developed to gather adequate and important data regarding weeks gestation and other known factors that may influence test results
( Appendix A).
3.) Diagnosis of bacterial vaginosis will be determined by using the CDC approved testing methods for diagnosis; Amsel’s criteria and FemExam.
4.) The FemExam and wet mount will be prepared and read by the same clinicians, using the same tools, to provide for consistency in diagnosis. The research clinicians will receive training to make sure everyone is performing the procedure in the same manner and the researcher will also calculate an interrater reliability coefficient.
5.) FemExam will be stored at 59-77 degrees Fahrenheit to ensure proper storage conditions and accurate results.
6.) Both wet mount and FemExam have been Clinical Laboratory Improvement Amendments (CLIA) approved, which allows nurse midwives to perform these tests in independent practice.
A sample of three hundred women will be recruited from Lifestages OB/GYN group of Dayton, Ohio. Permission to undertake this research will be obtained from the Chief Executive Officer, the Medical Director, the Primary Care Providers and the staff of this facility.
Population of interest
The target population of interest includes all pregnant women who initiate prenatal care between 12 to 16 weeks gestation. The Centers for Disease Control (1998) recommended the time for screening for bacterial vaginosis is during the early portion of the second trimester of pregnancy.
Entry to site/access to population
The researcher is a SNM affiliated with Lifestages OB/GYN practice participating in the study, and thus has access to the study population.
All women presenting for their first prenatal visit between 12 to 16 weeks gestation will be ask to participate. This convenience sample of pregnant women will be tested for bacterial vaginosis using both the wet prep and FemExam methods for diagnosis. This convience sample of women represent an appropriate target population because bacterial vaginosis occurs primarily in women who are of childbearing years. This strategy for selecting the convience sample is inexpensive, accessible, and less time consuming than many other types of samples.
The Questionnaire (Appendix A) and The Informed Consent (Appendix B) will be obtained prior to inclusion of the subject into the study. If the woman response to question #8 on the questionnaire form is "yes", then she will automatically be excluded from the study. Vaginal bleeding will render the pH results inaccuarate for both the FemExam and Amsel's criteria. Blood is alkaline, therefore the pH results will always be >4.5.
A convenience sample of pregnant women initiating prenatal care during their 12th to 16th week gestation will be evaluated for appropriate inclusion into the study. The CNM conducting the initial prenatal visit will date the pregnancy and review the questionnaire to determine the subject's appropriateness for this study. Convience sampling is of value to this study because of the availability of subjects. The convenience sample is easily accessed which makes the research feasible and relatively inexpensive. These available subjects will be typical of the population in terms of being at risk for bacterial vaginosis. Using this method will allow the researcher to examine variables in a currently occurring situation. No attempt will be made to control or manipulate the situation. Conducting research under real life conditions allows the researcher to draw conclusions and make inferences within a particular situation at the same time the study is being conducted. This type of research helps to guide thinking in terms of the study's clinical relevance and also helps direct further research.
Permission and approval for this study will be sought from the IRB of Philadelphia University, and the clinical site to ensure that the human subject’s rights are protected. The participants will be fully informed about this research and what it includes, and the benefits to hopefully be gained in enabling providers to learn of the best diagnostic test available. Because recent literature has linked bacterial vaginosis to preterm labor, any woman who is diagnosed with bacterial vaginosis will be treated (Eschenbach, 1998; Hammill, 1999; Riduan, 1993). In addition, if other vaginal infections are diagnosed during this research procedure such as candida or trichomonias, the subject will be informed of these results and referred to her health care provider. Due to the personal nature of this study, confidentiality is the predominant ethical consideration to this study. The subject’s identity and the data forms will be coded for data entry. The codes will only be known to the researcher who will keep this information locked and secured until the study is over. At that time the identifying information will be destroyed and never disclosed by the researcher in any manner. All qualifying women will be invited to participate in this study and ask to sign an informed consent.
Data collection procedures
The current volume of women presenting for their first prenatal visit between 12 to 16 weeks gestation is approximately forty women per month. Considering the sample size of three hundred women needed for this study, the researcher anticipates approximately nine months for the completion of gathering the data. This is taking into consideration that not every woman will give consent to participate in this research.
Diagnosis of bacterial vaginosis will be made according to the described criteria for wet mount and the FemExam card. Samples for diagnosis will be collected using three cotton-tipped swabs from the posterior lateral vaginal sidewalls. The procedure for each sample collected is described below.
Wet Mount- Add 2 drops of saline solution to one slide. Add two drops of KOH to another slide. Using the sample collected take one of the cotton-tipped swab and directly apply the vaginal fluid to saline slide. Make 2-3 rotations of swab in saline to ensure a fairly dilute sample. Apply the moistened cotton-tipped swab into the KOH fluid. Pass cotton-tip of KOH under nose for a quick whiff before discarding. Take the another cotton-tipped swab on roll it onto the pH test paper. Inspect the first slide for the presence of Clue cells.
FemExam- Remove test card from the foil pouch. Using the sample collected take one of the cotton-tipped swab and directly apply the vaginal fluid to the FemExam test card. Using a circular motion, gently rub the moistened swab over the entire surface of the amine test starting from the outside black ring and proceeding towards the center of the yellow circle. Then repeat this application moistening the amine test zone. The pH zone must be swabbed prior to swabbing the Amines zone. Results may be read within two minutes (Matria, 2000). FemExam can also diagnose candidiasis.
Description of each instrument and its reliability and validity
FemExam- Described under Research Design. FemExam must be stored at 59-77 degrees Fahrenheit to ensure accurate results. The sensitivity and specificity of FemExam TestCard are over 80%, (Matria, 2000).
Microscope- Recognition of Clue cells is an excellent predictor of BV. Microscopy is subject to variability depending upon the quality of the microscope, the adequacy of the specimen, and the skill of the observer. Microscopy has a sensitivity of 76% and a specificity of 71% when used to diagnose BV (Matria, 2000).
pH test strip- The pH paper is interpreted by comparing the paper with the color panel found on the package, which leaves room for over- or under-read pH. Commercial pH test strips have a poor capacity for distinguishing a pH of 4.6, which is considered to be within normal range for vaginal fluid, from a pH of 4.7, which is indicative of a bacterial or protozoal infection.
Data collector'sr olfactory senses– The data collector's ability to detect trimethylamine or volatile amines from a vaginal fluid sample is subjective and varies from person to person.
Every data collector in the study will be tested for interrater reliability. During the training sessions the data collector's will be independently observed by two raters with at least ten subjects using proper protocol and procedure developed for the study. This will help to insure a clear, consistent, and specific means for data collection. The data collected will be recorded using a nominal-scale measurement.
Data analysis plan
The data collected for this study will be obtained by the midwives of Lifestages OB/GYN.
Midwives are experienced health care providers that are approved by CLIA to perform microscopy and FemExam. The procedures for collecting and testing samples will be standardized The data will be categorized and reported using contingency tables. The nominal data obtained to test for Amsel's criteria would be best organized using a Chi-square analysis. Using this strategy, one can compare two or more categories of one variable to two or more categories of a second variable for significant differences between the samples. The associative statistical null hypothesis for this research states: There is no difference in the accuracy of the FemExam and Amsel's criteria.
Plan for disseminating findings
The results of this study will be presented to Matria Healthcare, Inc. Plans for disseminating findings will include a prepared manuscript for publication in a the Journal of midwifery & Women's Health. In addition, the findings will be presented to the Southern Ohio Chapter of midwifery at one of their regularly scheduled meetings.
Allen-Davis, J., (1998). Why we can't diagnose based on symptoms alone. OBG Management. (Suppl.) 2-5.
Association of Professors of Gynecology and Obstetrics (APGO). (1996). APGO Educational Series in Women's Health Issues; Diagnosis of Vaginitis. [Brochure]. Washington, DC: Curatek Pharmaceuticals.
Benrubi, G. (1999). Bacterial vaginosis: Diagnosing and treating the most common vaginal infection. The Female Patient. (Suppl.) 4-8.
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Briselden, A.M., Hillier, S.L. (1994). Evaluation of Affirm VP Microbial Identification test for gardnerella vaginalis and trichomonas vaginalis. Journal of Clinical Microbiology, 32, 148-152.
Centers for Disease Control and Prevention. 1998 Guidelines for Treatment of Sexually Transmitted Diseases. MMWR 1998;47(No. RR-1). Atlanta: CDC, 1998.
Eschenbach, D.A. (1998). Bacterial vaginosis: The case for screening high-risk gravidas. Optimal Diagnosis of Vaginitis. (Suppl.) 16-19.
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Hammill, H., (1999). Bacterial vaginal infections in the pregnant patient; diagnosis and management. The Female Patient. (Suppl.) 25-28.
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Jelovsek, F. (2000). Bacterial vaginal infections in pregnancy. In Woman's Diagnostic Cyber [On-line], Available: http://www.wdxcyber.com/npapvg11.htm
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Matria. (2000). FemExam pH and amines testcard: Frequently asked questions. Marietta, GA: Matria Healthcare.
McGregor, J.A., French, J. (2000). Bacterial vaginosis in pregnancy. Obstetrical and Gynecological Survey, 55 (5) (Suppl. 1), 1-19.
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Muller, E., Berger, K., Dennemark, N., Oleen-Burkey, M. (1999). Cost of bacterial vaginosis in pregnancy: Decision analysis and cost evaluation of a clinical study in Germany. Journal of Reproductive Medicine, 44, 807-814.
Pearson, C. (1998). Is there a low tech solution to preterm labor (for some women)? Network News. [On-line], Available: http://proquest.umi.com/pqdweb.
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Saling, E. (1998). Basic aspects of prematurity prevention and results achieved by a suitable, simple program. Journal Perinatal Medicine, 26 (6), 466-468.
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Thank you for your time and willingness to participate in this study and fill out this questionnaire.
1.) What was the first day of your last menstrual period (month and day)? ___________________
2.) Within the past 2 months, have you been diagnosed with a vaginal infection?______________.
If yes, which one (s)?
Yeast Bacterial Vaginosis Trichomonas Other__________
3.) Have you ever used a medication to treat a vaginal infection? ____________
If yes, when was the last time? ____________________
4.) Have you ever used a douche?_______________
If yes, when was the last time?__________________
5.) Have you recently (in the past month) had sex with a new partner? _______
6.) Have you ever had a sexually transmitted disease? ______
If yes, which one (s)?
Herpes Gonorrhea Chlamydia Syphilis Trichomonas HIV
7.) Are you experiencing any of the following symptoms?
Yes No Itching or burning
Yes No Unpleasant vaginal odor
Yes No Increased discharge
Yes No Discharge that is thick, white, and cottage cheese-like
Yes No Discharge that is thin, milky-white, or gray
Yes No Discharge that is yellow-green and frothy
Yes No Other symptoms (please describe):_____________________________________
8.) Are you experiencing any vaginal bleeding at this time?_______ ______________________________________________________________________
Appendix BPhiladelphia University IRB No. 123
CONSENT FOR PARTICIPATION IN DIAGNOSING BACTERIAL VAGINOSIS RESEARCH
I , ___________________________, consent to participate in research entitled
“THE ACCURACY OF WET MOUNT COMPARED TO FEMEXAM IN DIAGNOSING BACTERIAL VAGINOSIS”
I understand that the purpose of this study is to examine the accuracy of diagnosing bacterial vaginosis during pregnancy. The wet prep and FemExam methods will be used. Although this study may not benefit me directly, it will provide information that will enable health care providers to better plan for the care of their clients in the future.
Bacterial vaginosis (BV) is the most prevalent form of vaginal infection of reproductive age women in the United States. It is not typically sexually transmitted. It affects as many as 25% of women in the United States. Although bacterial vaginosis can cause mild symptoms, such as a thin gray discharge and possible “fishy” odor, as many as 50% of women with BV are asymptomatic. Several obstetrical complications have been linked to bacterial vaginosis. Recent studies have shown an association between the presence of BV during pregnancy and preterm birth. Any women diagnosed with bacterial vaginosis, or any other vaginal infection, will be referred to her health care provider for treatment.
I acknowledge that I have had the opportunity to obtain additional information regarding this study and that all questions I have raised have been answered to my full satisfaction. Participation in this study will not require any additional time from you as all screening will be conducted during your regular prenatal appointment. Obtaining the sample of vaginal secretions will be conducted during the routine pelvic/pap examine. This routine screening is considered standard of care and not an extra procedure. Further, I understand that participation in this study will in no way affect the care given to me during the course of this pregnancy.
Finally, I acknowledge that I fully understand the consent form. My participation in this study is strictly voluntary. A copy of this consent has been given to me. To protect human rights, I understand that this research proposal was reviewed and approved by the appropriate people, review boards at Philadelphia University, as well as LIFESTAGES OB/GYN practices, and affiliated hospitals.
The data obtained from this study will be coded and your identity will not be revealed while the study is being conducted, reported or published. After the study is completed, all identifying data will be destroyed. For further questions or concerns, call 1-937-885-4700 or e-mail Scar691007@aol.com.
Secretarial time to prepare questionnaires, consents, and data collection forms_________$600.00
Printing of questionnaires, consents, and data collection forms_____________________ $700.00
Assistance with statistical analysis of study data_________________________________$600.00
Statistical software SPSS___________________________________________________$300.00
Training cost for research assitants___________________________________________$300.00
FemExam TestCards ($5.00/card)___________________________________________$1500.00
Wet Prep Supplies (slides/pH paper/KOH & saline solutions/cotton-tipped swabs)_____ $250.00
Clinicians time (based on CNM’s salary, .20 FTE, approx. 9mths)__________________$ 9,000.00
Total = $ 13,250.00
Proposal for IRB approval / approval from Lifestages----------------------------- 1 month
Proposed time to complete study------------------------------------------------------ 9 months
Data entered and cleaned---------------------------------------------------------------- 3 months
Analysis of Data Entry_----------------------------------------------------------------- 3 months
Writing up formal report -------------------------------------------------------------- 3 months
Total time for completion---------------------------- 1 year, 7 months
Demographic Data Form
Please circle appropriate information
Native American Indian
Asian / Pacific Islander
Not married, in a mutually monogamous relationship
Less than high school
High School graduate or GED
Technical or vocational training
Subject ID# and Results
FemExam Amsel's Criteria
|Subject ID #|| pH >4.5 (+/-)|| Amines (+/-)|| pH > 4.5|| Whiff test|
| Thin |
| Clue Cells|
. . . . . . .