The advantages of UK Biobank's open-access strategy for health research.

Ready access to health research studies is becoming more important as researchers, and their funders, seek to maximize the opportunities for scientific innovation and health improvements. Large-scale population-based prospective studies are particularly useful for multidisciplinary research into the causes, treatment and prevention of many different diseases. UK Biobank has been established as an open-access resource for public health research, with the intention of making the data as widely available as possible in an equitable and transparent manner. Access to UK Biobank's unique breadth of phenotypic and genetic data has attracted researchers worldwide from across academia and industry. As a consequence, it has enabled scientists to perform world-leading collaborative research. Moreover, open access to an already deeply characterized cohort has encouraged both public and private sector investment in further enhancements to make UK Biobank an unparalleled resource for public health research and an exemplar for the development of open-access approaches for other studies.

Communications during epidural catheter placement for labour analgesia.

Evidence suggests that anaesthetists' communication can affect patient experience. There is a lack of guidance for anaesthetists as to the optimal verbal communication to use during insertion of epidurals on the labour ward. We recorded the verbal communication used by 14 anaesthetists during the siting of epidural catheters in women on the labour ward; a classification of the language used was subsequently devised. We found that commands and information statements were the most common types of communication used. Individual anaesthetists differed markedly in their use of positive and negative verbal language. This classification of verbal communication that we produced may be of value in future training and research of verbal communication used by anaesthetists on the labour ward.

Use of an expanded gold standard to estimate the accuracy of colposcopy and visual inspection with acetic acid.

We estimate the accuracy of colposcopy and visual inspection with acetic acid (VIA) while minimizing the effects of misclassification bias, and maximizing ascertainment of disease. VIA was performed by experienced physicians on a population-based sample of women aged 30 to 49 years in rural Shanxi province, China. Each woman received VIA, liquid-based cytology (LBC) and hybrid capture 2 (hc2, QIAGEN, Gaithersburg, MD; formerly Digene Corporation). Any woman who tested positive on any test had colposcopy, endocervical curettage (ECC) with directed biopsies as necessary and 4-quadrant random biopsies from normal-appearing areas of the cervix. A standard diagnosis based on colposcopy and directed biopsy, and an expanded diagnosis including ECC and 4-quadrant random biopsy were generated for each woman. In 1,839 women, use of the expanded versus the standard diagnostic criteria increased the prevalence of histologically confirmed high-grade cervical intraepithelial neoplasia and cancer (CIN2+) from 3.2% (59/1,839) to 4.2% (77/1,839) and decreased the sensitivity of VIA for CIN2+ from 69.5% (95% CI: 56.8-79.8) to 58.4% (95% CI: 47.3-68.8%) with little change in specificity of approximately 89%. Compared with the expanded diagnostic criterion, the sensitivity of a visual diagnosis of high-grade CIN or cancer by a colposcopist was 49.4% (95% CI: 38.2-60.5). The use of an expanded diagnostic criterion in this study yielded more conservative estimates of the sensitivity of VIA and colposcopy.

Colposcopists' agreement on cervical biopsy site.

OBJECTIVE: To determine the inter-observer agreement among colposcopists on the most abnormal area of the cervix from which a biopsy would be obtained and whether any attributes predict agreement. MATERIAL AND METHODS: Fifty cervigrams were reviewed and 72 colposcopists from five countries indicated the site to biopsy and whether an ECC should be obtained. Prior to the study, six Canadian colposcopists met to achieve consensus on the most diseased area for biopsy. Consensus was also reached on whether an ECC was indicated. For each cervigram, percent agreement was determined between each study colposcopist and the consensus. Data were analyzed to determine the attributes associated with the consensus response. RESULTS: The percent overall agreement of the colposcopists with the consensus diagnoses had a mean of 0.70 (95% CI, 0.65-0.75). The use of ECC was most common in Canada (15% of cases). The following factors were assessed by multivariate analysis to determine their influence on individual agreement with the consensus recommendation for the site to biopsy: country, duration of practice (less than or greater than 1 year), professional group (nurse, family doctor, pathologist, gynecologist, gynecologic oncologist), expert status (recognized national/international expert vs colposcopist), and gender. No factor was significantly associated. CONCLUSION: This international study was feasible and the level of inter-observer agreement among colposcopists on the location of the most severe lesions in cervical images is good.

Effectiveness and efficiency of selective vs universal screening for chlamydial infection in sexually active young women.

BACKGROUND: Since chlamydial cervicitis is not associated with specific complaints, screening asymptomatic women is an important initiative to prevent pelvic inflammatory disease and its sequelae. Compared with universal screening, selective screening is less costly but less effective so the cost savings vs the consequences of missing infected women need to be weighed carefully. METHODS: In two family planning clinics, 1002 women were surveyed for chlamydial infection (prevalence, 7%) and its predictors to determine whether universal or selective screening is the most efficient strategy. Two rules for the selection of patients were determined by logistic regression modeling and their relative efficiencies were compared by incremental cost-effectiveness and sensitivity analysis. The validity of the screening rules was tested in 191 students attending a university health clinic. RESULTS: If those with cervical friability, suspicious discharge, urinary frequency, or intermenstrual bleeding had been tested, 55.3% of all women would have been screened and 83.3% of all cases would have been detected. If those reporting a new sex partner in the preceding year had also been tested, 75.4% would have been screened, identifying 93.3% of all cases. The predictive power and practicality of the selection rules were validated in the university health clinic sample. Sensitivity analyses showed selective screening using cervical enzyme immunoassay with blocking confirmation was efficient if the prevalence of chlamydial infection was 16% or less, 11% or less, or 5% or less depending on whether base analyses, overestimated costs, or worst performance scenarios, respectively, were used. CONCLUSIONS: Selective screening based on four or five predictors and confirmed cervical enzyme immunoassay is an effective and efficient strategy in low prevalence settings.

Experience using cryotherapy for treatment of cervical precancerous lesions in low-resource settings.

Cervical cancer can be successfully prevented if timely identification of precancerous lesions is followed by effective treatment. In many developing countries, treatment of precancer is neglected because therapeutic services are unavailable, inaccessible, inappropriate, or inadequately linked to screening services. One of the main focuses of the Alliance for Cervical Cancer Prevention (ACCP) has been to ensure that safe and effective methods of treatment for precancer are both available and accessible to women who need them. Cryotherapy, in use for the past 40 years, is a relatively simple, safe, effective, acceptable, and appropriate outpatient procedure for the treatment of precancer. ACCP studies conducted in more than a dozen developing countries show that cryotherapy for precancer can be performed safely and effectively as an outpatient procedure at all levels of health facilities by trained and competent midlevel providers, thus increasing availability and accessibility to precancer treatment services.

Training for cervical cancer prevention programs in low-resource settings: focus on visual inspection with acetic acid and cryotherapy.

The modern approach to cervical cancer prevention, characterized by use of cytology and multiple visits for diagnosis and treatment, has frequently proven challenging and unworkable in low-resource settings. Because of this, the Alliance for Cervical Cancer Prevention (ACCP) has made it a priority to investigate and assess alternative approaches, particularly the use of visual screening methods, such as visual inspection with acetic acid (VIA) and visual inspection with Lugol's iodine (VILI), for precancer and cancer detection and the use of cryotherapy as a precancer treatment method. As a result of ACCP experience in providing training to nurses and doctors in these techniques, it is now widely agreed that training should be competency based, combining both didactic and hands-on approaches, and should be done in a clinical setting that resembles the service-delivery conditions at the program site. This article reviews ACCP experiences and perceptions about the essentials of training in visual inspection and cryotherapy and presents some lessons learned with regard to training in these techniques in low-resource settings.

A critical assessment of screening methods for cervical neoplasia.

The objective of cervical cancer screening is to reduce cervical cancer incidence and mortality by detecting and treating precancerous lesions. Conventional cytology is the most widely used cervical cancer screening test. Although cytology has been effective in reducing the incidence of and mortality from cervical cancer in developed countries in both opportunistic and--more dramatically--organized national programs, it has been less successful and largely ineffective in reducing disease burden in low-resource settings where it has been implemented. Liquid-based cytology, testing for infection with oncogenic types of human papillomaviruses, visual inspection with 3-5% acetic acid, magnified visual inspection with acetic acid, and visual inspection with Lugol's iodine have been evaluated as alternative tests. Their test characteristics, and the applications and limitations in screening, are discussed with an emphasis on the work of the Alliance for Cervical Cancer Prevention over the past 5 years.

Consent for labour epidural analgesia: an observational study in a single institution.

There is a wide range of practice amongst obstetric anaesthetists when obtaining consent for women requesting labour epidural analgesia. This is the first prospective observational study recording the number and types of risks mentioned and whether the risk was quantified. Statements of benefits and alternatives to the procedure were also noted. Fourteen anaesthetists, each consulting a single patient, were recorded during the process of obtaining consent and inserting the epidural. The most commonly mentioned risks (median 7) were headache/dural puncture, failure/difficulty with insertion, nerve damage, bleeding/haematoma and infection/epidural abscess. There was no difference between consultants and trainees, although consultants showed greater variance. It was uncommon for anaesthetists to state a benefit (21%) or mention an alternative option (21%), but there was usually a quantitative statement of risk (71%). Data showed a deviation from the Australian and New Zealand College of Anaesthetists guidelines and these findings may encourage anaesthetists to reflect on their own practice and guide future research.

Predictors of positivity for hepatitis B and the derivation of a selective screening rule in a Canadian sexually transmitted disease clinic.

OBJECTIVES: To determine the prevalence of hepatitis B surface antibody (anti-HBs) and antigenemia (HBsAg), the risk factors for seropositivity and the effectiveness of a selective serologic screening rule among sexually transmitted diseases (STD) clinic attendees. STUDY DESIGN: Clients in the Hamilton STD Clinic were surveyed from October 1992 to July 1993 on sociodemographic, past medical, and behavioural data, were tested for several STDs and were offered serological testing and vaccination against hepatitis B. Predictors of seropositivity were determined by single variable analysis. A selective serologic screening rule was derived using logistic regression modelling. RESULTS: The seroprevalence of anti-HBs was 6.8% (21/310) in the 310 of 385 clients (80.5%) who agreed to be tested and interviewed. There were no HBsAg carriers. Five independent risk factors were identified by logistic regression: (1) age greater than 35 years; (2) birth outside Canada and histories of; (3) syphilis; (4) gonorrhoea; or (5) injection drug use. If clients with at least one of these predictors had been tested, 34.5% would have been selected for serologic testing and 85.7% of all positives would have been detected. The screening rule was more effective for men than for women. CONCLUSION: In this low prevalence setting, selecting STD clinic clients based on the presence of any one of five risk predictors appears to be an effective strategy for hepatitis B serologic screening in the context of a Canadian vaccination program.

Observer variability in the scoring of colpophotographs.

Colposcopy and cervicography are accepted tools for assessing the cervix for an atypical transformation zone. We studied the validity of the colpophotograph as a measurement tool by determining the agreement of experienced colposcopists using colpophotographs of 50 women. Interobserver agreement was generally fair to good (kappa greater than or equal to 0.40) for the presence of the squamocolumnar junction and the area of ectopia but it was poor (kappa less than 0.40) for the area, border, and color characteristics of an atypical transformation zone. Intra-observer agreement was fair to good for the color characteristics of an atypical transformation zone, but it was poor for the area and border characteristics. We conclude that observer agreement studies should play a role in the validation of methods used in the visual diagnosis of cervical intraepithelial neoplasia. Considerable lack of agreement in reporting cytologic findings is a well-known problem, and lack of agreement might be an even bigger problem in reporting colposcopic findings.

Assessment of the cervix after acetic acid wash: inter-rater agreement using photographs.

OBJECTIVE: To estimate the inter-rater agreement on the assessment of cervical photographs after acetic acid wash, using visual inspection with acetic acid categories. METHODS: Three raters individually assessed 144 photographs as negative, positive, or suspicious for cancer. The inter-rater agreement was analyzed using the unweighted and weighted kappa coefficient. To explore the reasons for concordancy and discordancy, photographs were compared on histologic evidence of cervical intraepithelial neoplasia and on testing for oncogenic types of human papillomavirus. RESULTS: Overall raw agreement among the three raters was 66.7% (96 of 144) with a kappa of 0.57 (95% confidence interval 0.48, 0.66). Pair-wise agreement using unweighted and weighted kappa was moderate to substantial: 0.54-0.60 and 0.56-0.63, respectively. There was concordance on negative in 25.7% (37 of 144) and on positive or suspicious for cancer in 41.0% (59 of 144). Cervical intraepithelial neoplasia II or III was not present on biopsy if photographs were concordant-negative, and the human papillomavirus test was less likely to be positive (relative risk 0.3; 95% confidence interval 0.2, 0.6) in concordant-negatives compared with concordant-positives, including suspicious for cancer. Cervical intraepithelial neoplasia II or III was more common in photographs that were concordant-positive, including suspicious for cancer, compared with discordants (relative risk 3.4, 95% confidence interval 1.5, 7.6). CONCLUSION: Based on photographs of the cervix taken after acetic acid wash, the level of agreement among raters using visual inspection with acetic acid categories was moderate to substantial, consistent with other commonly used tests.

Tubal factor infertility: an association with prior chlamydial infection and asymptomatic salpingitis.

In 265 Canadian women, with and without tubal factor infertility (TFI), we compared Chlamydia trachomatis cultures of endocervical swabs, endotubal swabs and biopsies, serology, and past history. A history of pelvic inflammatory disease (PID) was absent in 69.2% of TFI women, despite visual evidence of tubal damage. C. trachomatis was not isolated in any of 52 patients with TFI (TFI group), 114 having tubal ligation (STER group), or 99 patients having hysterectomy (HYST group). However, chlamydial antigen was detected with an immunochemical method in 1 of 16 tubal biopsy specimens from TFI women. The prevalence of chlamydial IgM or IgG antibody in serum was significantly higher (P less than 0.0001) in the TFI group (79.1%) than in the other two groups (relative odds, 6.3; 95% confidence interval: 2.5, 16.8). In seropositive (IgG or IgM) subjects, there was a significant (P = 0.003) and strong (relative odds, 5.1; 95% confidence interval: 1.5, 18.1) association between chlamydial IgA antibody and TFI. In women with TFI, there was no significant association between IgM or IgG seropositivity (P = 0.56). or IgA seropositivity (P = 0.53), and a negative history for PID. These findings are consistent with the hypothesis that C. trachomatis is a major cause of TFI following PID, which may or may not be asymptomatic.

Detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Ureaplasma urealyticum, and Mycoplasma genitalium in First-void Urine Specimens by Multiplex Polymerase Chain Reaction.

Background: Sexually transmitted diseases are often caused by one or more microorganisms, and asymptomatic carriage and transmission may be of significance. Testing for more than one organism in a single assay could be a useful approach to laboratory diagnosis. Methods and Results: A multiplex polymerase chain reaction (PCR) assay was developed that employed specific primers targeted to the 7.5-kb cryptic plasmid of Chlamydia trachomatis, the cppB gene of the 4.2-kb cryptic plasmid of Neisseria gonorrhoeae, the 140-kd major adhesion protein gene of Mycoplasma genitlium, and the urease gene of Ureaplasma urealyticum. All four polymerase chain reaction products were detectable by agarose gel electorphoresis and were confirmed by Southern hybridization using fluorescein isothiocyanate-labeled oligonucleotide probes and enhanced chemiluminescent detection. Using purified DNA preparations, multiplex PCR had a reproducible detection limit of 1 fg of C. trachomatis DNA, 100 fg of N. gonorrhoeae DNA, and 10 fg U. urealyticum DNA and M. genitalium DNA, which converts to 1-2 genomic equivalents (ge) of C. trachomatis and N. gonorrhoeae, 4 ge of M. genitalium, and 10 ge U. urealyticum. Multiplex PCR was compared with individual uniplex polymerase chian reaction PCR assays by testing 117 first-void urine samples (91 men, 26 women) from Canadian or Kenyan patients. Multiplex PCR detected 45 of 46 (97.8%) urines with C. trachomatis DNA, 42 of 42 (100%) urines with N. gonorrhoeae DNA, 17 of 17 (100%) urines with U. urealyticum DNA, 4 of 4 (100%) urines with M. genitalium DNA, 12 of 12 urines that had DNA from two bacteria, and 2 of 2 urines with DNA from three bacteria. Multiplex PCR correctly identified bacteria in 92 of 93 urines for an overall sensitivity of 98.9%. Specificity calculations were 100% for C. trachomatis (71/71), N. gonorhoeae (75/75), U. urealyticum (100/100), and M. genitalium (113/113). Conclusions: Multiplex PCR provided a single sensitive and specific test for the detection of four bacteria in first-void urine samples. Testing of first-void urine samples by multiplex PCR could facilitate studies aimed at improving our understanding of the epidemiology of these important sexually transmitted diseases.

Imiquimod 5% cream is a safe and effective self-applied treatment for anogenital warts--results of an open-label, multicentre Phase IIIB trial.

Our objective was to determine the efficacy and safety of imiquimod 5% cream in the treatment of external genital/perianal warts in an open-label Phase IIIB trial. Patients applied imiquimod 5% cream 3 times per week, for up to 16 weeks. Those who cleared their warts were monitored during a 6-month follow-up period. If their warts recurred, or new warts developed during this time, patients could be re-treated for up to 16 additional weeks. Patients who experienced partial clearance during the initial treatment period entered an extended treatment period of up to an additional 16 weeks. A total of 943 patients from 114 clinic sites in 20 countries participated in this study. Complete clinical clearance was observed in 451/943 (47.8%) patients (intent-to-treat (ITT) analysis) during the initial treatment period, with clearance in an additional 52 (5.5%) patients during the extended treatment period beyond 16 weeks. The overall clearance rate for the combined treatment periods was 53.3%. In a treatment failure analysis, the overall clearance rate was 65.5%; a greater proportion of female patients (75.5%) experienced complete clearance than male patients (56.9%). Low recurrence rates, of 8.8% and 23.0%, were observed at the end of the 3- and 6-month follow-up periods, respectively. The sustained clearance rates (patients who cleared during treatment and remained clear at the end of the follow-up period) after 3 and 6 months were 41.6% and 33.0% (ITT analysis), respectively. Local erythema occurred in 67% of patients. In the majority of patients local skin reactions were of mild to moderate severity. In conclusion, imiquimod 5% cream is an effective self-applied treatment for external genital/perianal warts when applied for up to 16 weeks and is well tolerated for up to 32 weeks.

Screening seniors for risk of functional decline: results of a survey in family practice.

OBJECTIVE: To measure functional status, determine risk of functional decline and assess consistency between responses and standardized instruments. DESIGN: A mailed survey which measured functional impairment, recent hospitalization and bereavement. A positive response on at least one of these factors indicated that the individual was "at risk" for functional decline. A random sample (n = 73) of "at risk" subjects (specifically, family practice patients aged 70 and older) were assessed by a nurse. RESULTS: The response rate was 89% (369/415), 59% of seniors were female and the mean age was 77.1 (SD = 5.5) years. Self-reported risk, based on activities of daily living (ADLs), was associated with impairment in at least one basic ADL (p < 0.0005) using a standardized instrument. The positive predictive value of the survey for ADL impairment was 65%. CONCLUSION: Response to a mailed survey was high and self-reported ADL risks were consistent with findings from standardized assessment tools.

Partner notification for sexually transmitted diseases: an overview of the evidence.

OBJECTIVE: To compare the effectiveness of alternative partner notification strategies for gonorrhea, chlamydia, syphilis, HIV and hepatitis B. DATA SOURCES: Studies were identified using MEDLINE, EMBASE, SCISEARCH and other databases, review of reference lists and personal contact with over 80 international experts. STUDY SELECTION: Studies with at least two comparison groups exposed to different partner notification strategies were included. DATA EXTRACTION: Methodological rigor was assessed, and information regarding study populations, interventions and outcomes was extracted independently by two reviewers. MAIN RESULTS: Twelve studies met our inclusion criteria; five were methodologically strong; seven provided data on the referral process; four provided data on trained interviewers compared with routine care providers; and three provided data on the interview process. CONCLUSIONS: Only limited, broad conclusions regarding the effectiveness of various partner notification approaches could be drawn from these comparative studies. Until newer data become available, practice guidelines must be based to a large extent on other grounds.

Partner notification for sexually transmitted diseases: proposed practice guidelines.

Using the results of an analysis of available scientific evidence and a survey of current practice in Canada, as well as expert opinion, these guidelines attempt to consider current partner notification practice in Canada and recommend an approach to determining practice which is flexible enough to address local circumstances. Priority areas for future research were also identified.

A survey of public health partner notification for sexually transmitted diseases in Canada.

OBJECTIVE: To describe the range of practice for sexually transmitted disease (STD) contact tracing/partner notification (PN) by public health agencies in Canada. METHODS: A two-level mailed survey, using two different questionnaires, was conducted from Aug. 1991 to Feb. 1992, directed to: 1) provincial and territorial epidemiologists/directors of STD control, asking about program organization; and 2) 154 local health units/provincially run PN programs, asking about practice patterns of STD partner notification. CONCLUSIONS: In Canada, STD PN by public health agencies is routinely practised in most provinces. PN efforts vary by the STD; less PN effort goes to chlamydia despite a high burden of illness; HIV PN is frequently perceived to be within the responsibility of the physician. For STDs with higher PN effort, the preferred method is provider referral. Targeting is seldom utilized, and there are little available data at a local level monitoring even process measures of effectiveness.

Confirmation of cervical neoplasia using a hand-held, lighted magnification device.

OBJECTIVES: The objective of this study was to estimate the sensitivity and specificity of visual inspection with acetic acid and magnification (VIAM) using the AviScope device to confirm high-grade cervical intraepithelial neoplasia or carcinoma. METHODS: VIAM was performed on 142 women aged 18-50 years referred to three colposcopy clinics because of abnormal cervical cytology. Each woman then had a colposcopic examination with cervical biopsy when indicated. RESULTS: The AviScope device identified 24 of the 40 women who had CIN 2, 3, or carcinoma, yielding a sensitivity of 60.0% (95% CI 43.4, 74.7). The AviScope correctly identified 60 of 87 women negative for dysplasia or cancer, yielding a specificity of 69.0% (95% CI 58.0, 78.2) compared with colposcopy and cervical histology. CONCLUSION: VIAM using the AviScope device was moderately sensitive and specific for the confirmation of high-grade cervical lesions in women referred with abnormal cervical cytology.