Validation of a claims-based algorithm identifying eligible study subjects in the ADAPTABLE pragmatic clinical trial.

OBJECTIVE: Validate an algorithm that uses administrative claims data to identify eligible study subjects for the ADAPTABLE (Aspirin Dosing: A Patient-centric Trial Assessing Benefits and Long-Term Effectiveness) pragmatic clinical trial (PCT). MATERIALS AND METHODS: This study used medical records from a random sample of patients identified as eligible for the ADAPTABLE trial. The inclusion criteria for ADAPTABLE were a history of acute myocardial infarction (AMI) or percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG), or other coronary artery disease (CAD), plus at least one of several risk-enrichment factors. Exclusion criteria included a history of bleeding disorders or aspirin allergy. Using a claims-based algorithm, based on International Classification of Diseases, 9th Edition, Clinical Modification (ICD-9-CM) and 10th Edition (ICD-10) codes and Current Procedural Terminology (CPT) codes, we identified patients eligible for the PCT. The primary outcome was the positive predictive value (PPV) of the identification algorithm: the proportion of sampled patients whose medical records confirmed their ADAPTABLE study eligibility. Exact 95% confidence limits for binomial random variables were calculated for the PPV estimates. RESULTS: Of the 185 patients whose medical records were reviewed, 168 (90.8%; 95% Confidence Interval: 85.7%, 94.6%) were confirmed study eligible. This proportion did not differ between patients identified with codes for AMI and patients identified with codes for PCI or CABG. CONCLUSION: The estimated PPV was similar to those in claims-based identification of drug safety surveillance events, indicating that administrative claims data can accurately identify study-eligible subjects for pragmatic clinical trials.

Withdrawal attitudes and experiences: a qualitative perspective among young urban adults.

CONTEXT: Withdrawal is a widely used pregnancy prevention practice, but is popularly regarded as ineffective. An in-depth study of withdrawal behaviors would improve understanding of its role in reproductive health care. METHODS: Ninety-five ethnically diverse males and females aged 18-25, recruited through family planning clinics and community outreach in a large U.S. city, participated in semistructured, open-ended interviews in 2006 and 2007. Interviews examined up to six heterosexual relationships and focused on contraceptive attitudes, norms and experiences. Transcripts were reviewed and coded, and key themes related to withdrawal were identified. RESULTS: Withdrawal was a popular contraceptive technique, but opinions on its effectiveness were mixed. Some participants (especially women) expressed anxiety concerning pregnancy risk due to perceived ineffectiveness of withdrawal, and women were concerned about their partner's capacity to consistently withdraw prior to ejaculation. Others described confidence and skill in using withdrawal, and considered it effective. Reasons for use of withdrawal included convenience and dissatisfaction with hormonal contraceptives and condoms. Withdrawal was described as an expected alternative to condoms in both casual and long-term relationships, and as a secondary, or backup, method with use of hormonal contraceptives or condoms. Participants had rarely discussed withdrawal with health care providers; knowledge about the method had generally come from less reliable sources, including peers. CONCLUSIONS: Health care provider discussions with patients about withdrawal could give greater insight into risk behaviors. More informed prevention counseling messages would be helped by better effectiveness estimates and understanding of factors most likely to result in withdrawal failure.

Young unmarried men's understanding of female hormonal contraception.

BACKGROUND: A better understanding of men's attitudes, norms and behaviors regarding women's use of hormonal contraception is needed. STUDY DESIGN: We conducted contraceptive life-history interviews with 41 ethnically diverse males ages 18-25 years which detailed up to six heterosexual relationships, focusing on knowledge, attitudes, norms and behaviors regarding hormonal contraception use, decision making and communication. RESULTS: Men's attitudes, norms and behaviors associated with hormonal contraceptive decisions and use varied greatly across participants and their relationships. Findings suggest a mixture of attitudes and practices regarding the importance of communication around contraception influenced by sexual experiences, age and relationship type. Many men demonstrated limited knowledge about contraceptives and identified improving contraceptive knowledge as an essential step in facilitating contraceptive communication. CONCLUSIONS: Increased awareness about young men's understanding of and perceived roles regarding hormonal contraception will help in designing services that address contraceptive adherence, contraceptive communication and incorrect or inadequate contraceptive knowledge.