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D G Ferris

Publications and source records attributed to D G Ferris.

At least 55 records · Page 3Linked to original sources
PubMed1993

Clinical decision-making following abnormal Papanicolaou smear reports.

OBJECTIVE: Interpretation of abnormal Papanicolaou smear reports and the subsequent management of the patient frequently present significant decision-making problems for clinicians. The purpose of this study was to evaluate family physician clinical decision-making strategies for abnormal cervical cytology reports using simulation techniques. METHODS: One hundred fifteen practicing family physicians evaluated two simulations of women with abnormal cervical cytology, the first with inflammatory cytology and the second with a high-grade squamous intraepithelial lesion. RESULTS: Most physicians (66%) selected an etiology evaluation and specific treatment approach to an inflammatory report, while 26% of respondents chose empiric treatment. For the high-grade squamous intraepithelial lesion simulation, 88% of physicians chose the appropriate management response of colposcopic evaluation. CONCLUSIONS: Practice experience, level of involvement, clinician gender, and type of cervical cytology classification influenced family physician clinical decision-making. The majority of responses to an inflammatory or high-grade squamous intraepithelial lesion report was appropriate based on current scientific data.

Adult↗
PubMed1993

Physician attitudes toward the Bethesda System of reporting cervical cytology.

OBJECTIVE: The purpose of this investigation was to determine family physicians' and gynecologists' attitudes toward and understanding of the Bethesda System, a new cervical cytology classification and reporting system. METHODS: A convenience sample of 159 family physicians and gynecologists completed a questionnaire that assessed attitudes, knowledge, and opinions about the Bethesda System. RESULTS: Compared with family physicians, gynecologists thought the Bethesda System was more likely to cause patient management problems (p < 0.001) and preferred not to combine viral cytologic effects with mild dysplasia when reporting a low-grade squamous intraepithelial lesion (p < 0.004). However, increased understanding of the system by physicians correlated with greater preference for the Bethesda System (p < 0.02). In this exploratory study, family physicians, rather than gynecologists, were more inclined to use the Bethesda System and perceived it as a means to reduce clinical evaluation and patient management problems. Gynecologists reported a fuller understanding of the Bethesda System, yet they were more critical of the cytology categorizations. Within each specialty, greater understanding of the Bethesda System led to its wider acceptance.

Adult↗
PubMed1993

Cervicography: adjunctive cervical cancer screening by primary care clinicians.

BACKGROUND: Cervicography is an adjunct method of cervical cancer screening intended to complement cervical cytologic sampling, ie, Papanicolaou (Pap) smear. Cervicography involves obtaining and evaluating a photographic image of the cervix. The purpose of this investigation was to evaluate the screening use of cervicography as an adjunct to clinical cytologic screening. METHODS: Women presenting at four clinical sites for annual cervical cytologic screening or for follow-up evaluation after receiving an abnormal Pap smear result were enrolled in the study. Each patient received a Pap smear and a cervigram. Those women in whom abnormalities were detected by either test subsequently underwent colposcopy, and when appropriate, histologic specimens were obtained. RESULTS: Pap smear and cervigram data were obtained for 1449 women. When premalignant or malignant histologic test results were considered as a true positive, the Pap smear correctly identified 25.6% of subjects with dysplasia and 37.5% with severe dysplasia. The Pap smear failed to identify the one patient with invasive cancer. The cervigram detected 50.5% of the subjects with dysplasia and 77.8% of the subjects with severe dysplasia, and it identified the one patient with invasive cancer when a positive cervigram was considered a true positive. When the results were combined, the two tests identified 62.9% of subjects with histologically confirmed dysplasia, 81.3% of subjects with severe dysplasia, and 100% (one patient) with cancer. CONCLUSIONS: The cervigram detected twice the number of patients with premalignant disease as the Pap smear alone, and correctly identified the invasive cancer. Cervicography improved the detection of cervical disease.

Adolescent↗
PubMed1993

Colposcopic accuracy in a residency training program: defining competency and proficiency.

BACKGROUND: The determination of proficiency in procedural skills has evoked keen interest, but meaningful guidelines are limited by the absence of pertinent clinical data. Colposcopic accuracy is defined as the clinical correlation between a colposcopic impression and a histologic report. The colposcopic accuracy of physicians in a university-based family practice residency colposcopy program was evaluated. METHODS: Demographic information, clinical findings, and laboratory results of patients evaluated by colposcopy were prospectively recorded. Colposcopic accuracy was calculated based on the agreement of the colposcopic impression with the histologic interpretation within one histologic grade. RESULTS: Colposcopic examinations were performed on 282 patients. Histologic evidence of premalignant cervical disease was identified in 115 patients as follows: mild dysplasia, 72; moderate dysplasia, 24; and severe dysplasia, 19. The colposcopic impression agreed within one histologic grade in 188 of 205 patients for a colposcopic accuracy rate of 91.7% (95% CI = 87.1% to 95.1%). CONCLUSIONS: Given an acceptable latitude of clinical correlation between the colposcopic impression and histologic interpretation, the colposcopic accuracy of family physicians compared favorably with that reported by other colposcopists. The more common colposcopic errors were overestimation of low-grade disease and underestimation of high-grade disease. Colposcopic accuracy at an essential minimal proficiency level of 80% should form the basis for assessing specialized perceptual ability and therefore determining colposcopic competency.

Adolescent↗
PubMed1993

Measurement of subjective phenomena in primary care research: the Visual Analogue Scale.

The visual analogue scale is a technique used to measure subjective phenomena. It is a self-reporting device consisting of a line of predetermined length that separates extreme boundaries of the phenomenon being measured. The purpose of this review is to report on the characteristics of the visual analogue scale technique, including its reliability, validity, accuracy, and scale value. This review presents several examples of the usefulness of the visual analogue scale technique in primary care research projects, describes its advantages and limitations, and presents suggestions for constructing visual analogue scales.

Affect↗
PubMed1992

Elementary school students' performance with two ELISA test systems.

OBJECTIVE: To examine analytic performance by previously untrained and inexperienced subjects using enzyme-linked immunosorbent assay (ELISA) tests developed for decentralized laboratories. Performance variability between tests assigned to the "simple" and "moderately complex" Health Care Financing Administration laboratory levels was evaluated. DESIGN: A nonrandomized trial of the Surecell Strep-A chorionic gonadotropin ELISA tests. Each subject processed nine unknown specimens (three negative, three weakly positive, and three strongly positive) for each ELISA test. Subjects were blinded to expected test results. SETTING: An elementary school. SUBJECTS: A convenience sample of 52 students enrolled in the sixth and seventh grades. This age group was chosen because of their ability to generally comprehend instructions and remain attentive to the testing task. INTERVENTIONS: Subjects were either self-trained by reading package insert directions or trained by a manufacturer's sales representative. MAIN OUTCOME MEASURES: Performance was measured as the percentage of correct test results for the unknown specimens. The sensitivity and specificity for each test by operator group were calculated. RESULTS: Subjects demonstrated an overall sensitivity of 97.1% and specificity of 94.7% for human chorionic gonadotropin unknown specimens and a 95.9% sensitivity and 96.8% specificity for group A streptococcus unknown specimens. No significant differences between the self-trained group and the representative-trained group were observed for either group A streptococcus or human chorionic gonadotropin tests. Performance was so high with the first specimen that improvement over time (ie, a "learning curve") could not be demonstrated. CONCLUSION: These ELISA test systems are able to achieve high levels of performance by subjects with no formal laboratory background, no previous method specific experience, and limited self-training.

Adolescent↗
PubMed1992

Colposcopy.

Explore the source record for details and available documents.

Clinical Competence↗
PubMed1992

The optimal technique for obtaining a Papanicolaou smear with the Cervex-Brush.

BACKGROUND: The Cervex-Brush (Rovers, The Netherlands; Unimar, Wilton, Conn) is a cervical cytologic sampling device used to simultaneously collect endocervical and ectocervical cells. The optimal method for using this device to collect cervical epithelial cells for a Papanicolaou smear has not been described in the medical literature. METHODS: Using the Cervex-Brush, Papanicolaou smears were collected from 516 women in a prospective randomized study to evaluate five different clockwise rotation techniques: 180 degrees rotation of the brush, 360 degrees, 720 degrees, 1080 degrees, and 1800 degrees. The Bethesda System of classifying Papanicolaou smears was used to report cytologic results. Endocervical cell presence as an indicator of smear adequacy was quantitated from 0 to 4+. RESULTS: As the number of rotations was increased, the number of endocervical cells collected also increased (P less than .05). Abnormal epithelial cells were found in 22.3% of the smears obtained by rotating the brush 1080 degrees and 1800 degrees. This was compared with abnormal cells found in 8.2%, 4.5%, and 11.5% of the smears collected by rotating the brush 180 degrees, 360 degrees, and 720 degrees, respectively (P less than .001). Two smears that identified high-grade squamous intraepithelial lesions were collected using the 1800 degrees rotation. Unsatisfactory smears were obtained in 39 (7.5%) of the 516 smears. The percentage of slides containing hemorrhagic artifact was greatest (16.4%) in the 1800 degrees rotation group, but the likelihood of the Papanicolaou smear being considered unsatisfactory was not increased (P less than .05). CONCLUSIONS: Using a clockwise 1800 degrees rotation of the Cervex-Brush to obtain a Papanicolaou smear maximized the collection of endocervical cells, detected the greatest percentage of abnormal cells, and did not statistically exceed the acceptable limit for hemorrhagic artifact.

Adolescent↗
PubMed1992

A comparison of three rapid chlamydial tests in pregnant and nonpregnant women.

BACKGROUND: The purpose of this investigation was to evaluate the performance characteristics of three rapid immunoassay tests to detect Chlamydia trachomatis cervicitis. METHODS: Endocervical samples from 506 women were evaluated using the three rapid immunoassay tests and the results were compared with those obtained by an endocervical chlamydial culture. RESULTS: The prevalence of C trachomatis cervicitis was 9.3%. Overall sensitivity and specificity of the Abbott TestPack Chlamydia test were 66.0% and 99.8%, respectively, of the Kodak Surecell Chlamydia test were 85.1% and 99.3%, respectively, and of the Unipath Clearview Chlamydia test were 85.1% and 98.5%, respectively. Pregnancy did not affect test specificity, but did influence sensitivity. The tests ranged from 5% to 22% less sensitive in nonpregnant women. CONCLUSIONS: The results of the investigation establish that the Clearview and Surecell chlamydial immunoassay tests performed well, particularly for pregnant women.

Adult↗
PubMed1992

Cryosurgical equipment: a critical review.

BACKGROUND: Cryosurgery is frequently used by family physicians to treat benign and premalignant epithelial disease. A professional medical team consisting of a practicing cryotherapist and a mechanical engineer independently critically evaluated the design, function, and performance of selected cryosurgical equipment. METHODS: Qualitative observations and quantitative measurements were performed on seven nitrous oxide cryosurgical units and one liquid nitrogen unit, representing seven manufacturers and distributors. Specific isotherm generation distributions, lateral spread of freeze and refreeze measurements, defrost intervals, recovery zone sizes, relative ease of use, and component characteristics were comparatively assessed. RESULTS: The in vitro mean lateral spread of freeze distance at 180 seconds varied between 5.8 mm for the Frigitronics CryoPlus and 4.6 mm for the Leisegang LM-900. The mean -20 degrees C isotherm generation time, measured by a thermocouple 3 mm lateral to the cryoprobe tip margin, ranged from 229 seconds for the Wallach WA-1000B to 361 seconds for the Spembly PCG 9R. Defrost times varied between 2 seconds for the Wallach WA-1000B and 320 seconds for the Brymill Mini-Cryogun. Refreeze time was quickest (36 seconds) using the GyneTech GT-1S. The mean in vitro recovery zones varied between 1.6 mm and 2.1 mm. CONCLUSIONS: This evaluation documented both differences and similarities among various cryosurgical units in terms of design, function, and performance. The Wallach, Frigitronics, and GyneTech nitrous oxide cryosurgical units demonstrated the best overall performance.

Cryosurgery↗
PubMed1991

Noninvasive detection of Chlamydia trachomatis urethritis in men by a rapid enzyme immunoassay test.

BACKGROUND: The purpose of this investigation was to evaluate the ability of a rapid enzyme immunoassay test to noninvasively detect Chlamydia trachomatis urethritis in men from a urine specimen. METHODS: Urethral samples and urine from 207 patients were evaluated. Urethral and urine sediment Gram stains, leukocyte esterase dipstick tests, and enzyme immunoassay analyses of centrifuged and uncentrifuged urine were compared with urethral C trachomatis culture. RESULTS: The prevalence of infection in this population was 10.3%. Sensitivity and specificity of the enzyme immunoassay on the centrifuged urine specimen were 70% and 96%, respectively. The positive and negative predictive values were 67% and 97%, respectively. The uncentrifuged urine enzyme immunoassay sensitivity was 35.7% and specificity was 98.9%. Leukocyte esterase test sensitivity compared with that of the Neisseria gonorrhoeae and/or C trachomatis cultures was 83.3%, and specificity was 52%. CONCLUSIONS: The rapid enzyme immunoassay clinically complemented the screening urine sediment Gram stain and the leukocyte esterase test. The judicious use of a noninvasive C trachomatis rapid enzyme immunoassay test to identify organism-specific urethritis may improve patient management of sexually transmitted disease.

Adult↗
PubMed1991

Colpophotography systems: a review.

Colpophotography and video colposcopy systems are useful for pathology documentation purposes, patient education, and colposcopy training. A wide variety of colposcopic visual media components are available to enhance routine colposcopy. Colpophotographic systems supplied by eight colposcope manufacturers were critically evaluated by a colposcopist and a medical photographer. Components were independently and objectively analyzed. Photographic examination considered color, illumination uniformity, and coverage of illumination at all possible colposcopic magnifications. Photographs were developed by a standardized technique. The investigation results clearly demonstrated variability between different colpophotographic systems. Quality colpophotography is dependent on certain colposcope features and potential modifications. Colpophotography and video colposcopy systems complement the standard colposcopic procedure.

Colposcopes↗
PubMed1991

Colposcopes: a critical review.

A multidimensional professional team consisting of a practicing colposcopist, a mechanical engineer, and a medical photographer independently critically evaluated the features of selected colposcopes. Qualitative observations and quantitative measurements were performed on 13 colposcopes representing eight manufacturers and distributors. Optical characteristics, ocular system operation, mobility and stability, relative ease of use, component characteristics, space for instrumentation, and visual illumination, uniformity, and color were comparatively assessed. The specific colposcope information provided may benefit practicing physicians or novice colposcopists who are contemplating purchasing a colposcope. The presented framework of critical feature evaluation may also facilitate the informed selection of other colposcopes not included in this selective, critical, comprehensive review.

Colposcopes↗
PubMed1990

A comparison of rapid enzyme immunoassay tests for the detection of Chlamydia trachomatis cervical infections.

Two rapid enzyme immunoassay test kits were compared with culture for the detection of Chlamydia trachomatis endocervical infections. Endocervical samples for C trachomatis culture and the two enzyme immunoassay tests were evaluated from 502 county health department and Planned Parenthood patients. The prevalence of infection in this population was 12%. Sensitivity and specificity of the Abbott TestPack Chlamydia were 51.7% and 99.5%, respectively, and of the Kodak Surecell Chlamydia were 76.7% and 98.6%, respectively. The positive and negative predictive values for TestPack were 93.9% and 93.8%, and for Surecell were 88.5% and 96.9%, respectively. Additionally, an in vitro investigation was used to evaluate whether typical office staff (physicians, nurses, medical technicians, receptionists, and radiology technicians) were able to perform competently the tests in each kit. Office personnel tested 12 dilutions of a C trachomatis stock sample or negative control sample as unknowns for each kit in the in vitro investigation. There were no differences among office staff in performance when compared for each test kit. Selective use of these enzyme immunoassay tests for high-risk patients in a family practice population that has a high prevalence of patients with C trachomatis infection may be helpful when rapid test results are required and cultures are not feasible. After appropriate training, most physician office personnel were equally able to perform the enzyme immunoassay tests evaluated.

Adult↗
PubMed1990

Test of cure for genital Chlamydia trachomatis infection in women.

Convenient, reliable tests of cure for genital chlamydial infections have not been evaluated. Cervical appearance, endocervical Gram stain, enzyme immunoassay, and culture for Chlamydia trachomatis were evaluated during a pretreatment visit and at two subsequent randomized test-of-cure visits for 64 nongravid women with endocervical C trachomatis of 3544 patients screened. There were no useful correlations between C trachomatis resolution and cervical appearance. Endocervical Gram stain was determined to be unreliable for test-of-cure use. Both C trachomatis culture and enzyme-linked immunosorbent assay (ELISA) were shown to be effective for test-of-cure evaluation. The ELISA test became reliably negative 10 days after initiation of treatment and 1 to 5 days after the clearance of viable organisms detected by culture (P = .03). Convenience and cost considerations favor antigen detection methods. This study suggests that antigen detection methods can be used for situations in which test of cure is indicated, such as therapy noncompliance, circumstances supporting reinfection, pregnancy, complicated infections, requests for psychological reassurance, and evidence of persistent cervicitis.

Chlamydia Infections↗