Steve Dooley


Estimating the Percentage of Workforce Health Programs in Ontario from Results of a Mail Survey at Different Follow-Up Stages


Selection bias due to non-respondents is a common concern in mail surveys. The authors developed a procedure to estimate characteristics of non-respondents based on when subjects respond using data from a survey of personnel managers from large Ontario companies. The study was designed to assess the nature and extent of employee assistance programs (EAPs) and health promotion initiatives. Results indicated that personnel managers who responded quickly were significantly more likely to have an EAP than those who responded later. Estimates of the proportion of non-respondents with EAPs were made by extrapolation, based on when people responded. The estimated proportion of non-responders with EAPs was nearly identical to the actual proportion as determined by follow-up telephone interviews. Analyses also showed that companies with EAPs were significantly more likely to have health promotion programs Extrapolation procedures were therefore used to estimate the proportion of companies with these other health promotion motion initiatives.