"Rainbow reviews." IV: Recent publications of the National Center for Health Statistics.

I am always impressed at the wealth of interesting and useful information available from the NCHS, if one knows where to look. The Center tries to adapt to the changing needs of the potential users of their data, including health planners and policy analysts, and academicians. This is illustrated by the increasing emphasis on medical care utilization, especially in long term care, on disease prevention and health promotion issues and on international comparisons. Clinical investigators should be familiar with the NCHS reports, if only to avoid duplication of effort. But beyond that, the information they present can be used to develop hypotheses, estimate variances for sample size determinations, and provide useful model instruments and methods. Beyond that, the NCHS does not analyze and report exhaustively on these data, if only because of lack of resources, so that it makes most of these data available for further research at a nominal charge. Many doctoral dissertations have been based on these tapes as the primary data source for detailed content analysis and/or for methodologic innovation.