Assesses the value of the Government Printing Office's 1983 "Biennial Survey" as a tool to support depository library planning and decision making. The survey data are evaluated in terms of reliability, validity, and utility, and recommendations are offered for improving the design, administration, and analysis of the survey. (CLB)

Discusses issues relating to the reliability, validity, utility, and information value of unobtrusive testing of library reference services; provides suggestions for practical applications of these criteria; applies study findings to library decision making and planning; and identifies topics for further methodological refinement. (Author/CLB)