ally has an important public health impact, since the findings did not have the intense internal peer review of the abbreviated process? Such questions could affect the perceived reliability and credibility of findings based on VSD data that are released by NIP-affiliated VSD researchers.

RELEASE OF PRELIMINARY FINDINGS

Standards of Practice for Preliminary Findings

To discuss whether, when, and how to release and share preliminary findings with others, it is necessary first to have a common understanding of what is meant by the term preliminary findings. For purposes of this report, preliminary findings refers to results or summaries and associated conclusions that are based on incomplete data or incomplete analyses. Because data are incorporated into the VSD database annually, concerns about preliminary findings affecting continual data accrual are not applicable here.

The question of the release of preliminary findings based on VSD data has an additional layer of complexity related to the multistage process that is used to test a hypothesis. In the VSD setting, preliminary findings may refer to results of the first-level analyses (based on automated data) or to results of incomplete analyses or incomplete data in second-level (case-control) studies.

Preliminary Findings Because of Incomplete Data

Data may be incomplete because the expected data have not all been collected, validated, or otherwise processed for analysis. In some literature, particularly that related to clinical trials, interim findings or preliminary findings refers to analyses of incomplete data that are expected to be repeated as data accumulate. In such circumstances, the statistical issues of multiple analyses of interim data have been examined, and methods for controlling false-positive error rates have been developed (DeMets, 2004). Repeated analyses of findings do not appear to be germane to the part of the committee’s charge on releasing preliminary findings, because these studies are not typically designed to incorporate additional data over time as events accumulate.

Preliminary Findings Because of Incomplete Analyses

Even with complete data, analyses may be incomplete because some protocol-specified analyses have not been conducted. Analyses of observational data usually progress along the following lines. Early in the pro-



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