Whereas random selection was thought to be too logistically complicated to realistically implement, the remaining methods with preselected days or times for enrollment were thought to be subject to selection bias resulting from families bringing their children during "study" times.
For each method, we recorded the total time required for enrollment, and the time required for manual transcription (paper) onto a computer database.
An analysis of the PROWESS data indicates that 36.2% of the 1690 PROWESS patients met the AEC without the 8-hour time restriction and 5.7% met the criteria with the 8-hour time restriction for enrollment in the study by Annane and coworkers [ 15].
The time period for enrollment and collection of patient data was predetermined based on funding and availability of the clinical partner and took place from February to December 2012.
The exchange worries that could create delays and health plan rates wouldn't be ready in time for annual enrollment, throwing the market into disarray.
Covered California, the state's Obamacare exchange, has warned that Proposition 45 could undermine its ability to negotiate rates with insurers and have health plans available in time for open enrollment.
Median follow-up time for survival (enrollment to data cutoff for analysis) for all patients was 72 weeks (range=52 113).
Demographic and laboratory data were extracted retrospectively from hospital records for mono-infected individuals or at time of enrollment for co-infected individuals.
Baseline data were collected at the time of enrollment for the subcohort patients and retrospectively for cases outside the subcohort.
Further, some studies estimate exposure relating to a short period in time, for example, time of enrollment into a cohort (Dockery et al. 1993; Pope et al. 1995; Vineis et al. 2006), whereas other studies use residential addresses over longer time periods as the basis for assessing exposure (Nafstad et al. 2003; Nyberg et al. 2000).
