Showing papers by "Colleen A. McHorney published in 1994"

The MOS 36-item Short-Form Health Survey (SF-36): III. Tests of data quality, scaling assumptions, and reliability across diverse patient groups.

Abstract: The widespread use of standardized health surveys is predicated on the largely untested assumption that scales constructed from those surveys will satisfy minimum psychometric requirements across diverse population groups. Data from the Medical Outcomes Study (MOS) were used to evaluate data completeness and quality, test scaling assumptions, and estimate internal-consistency reliability for the eight scales constructed from the MOS SF-36 Health Survey. Analyses were conducted among 3,445 patients and were replicated across 24 subgroups differing in sociodemographic characteristics, diagnosis, and disease severity. For each scale, item-completion rates were high across all groups (88% to 95%), but tended to be somewhat lower among the elderly, those with less than a high school education, and those in poverty. On average, surveys were complete enough to compute scales scores for more than 96% of the sample. Across patient groups, all scales passed tests for item-internal consistency (97% passed) and item-discriminant validity (92% passed). Reliability coefficients ranged from a low of 0.65 to a high of 0.94 across scales (median = 0.85) and varied somewhat across patient subgroups. Floor effects were negligible except for the two role disability scales. Noteworthy ceiling effects were observed for both role disability scales and the social functioning scale. These findings support the use of the SF-36 survey across the diverse populations studied and identify population groups in which use of standardized health status measures may or may not be problematic.

Comparisons of the costs and quality of norms for the SF-36 health survey collected by mail versus telephone interview: results from a national survey.

Abstract: Many health status surveys have been designed for mail, telephone, or in-person administration. However, with rare exception, investigators have not studied the effect the survey mode of administration has on the way respondents assess their health and other important parameters (such as response rates, nonresponse bias, and data quality), which can affect the generalizability of results. Using a national sampling frame of noninstitutionalized adults from the General Social Survey, we randomly assigned adults to a mail survey (80%) or a computer-assisted telephone survey (20%). The surveys were designed to provide national norms for the SF-36 Health Survey. Total data collection costs per case for the telephone survey ($47.86) were 77% higher than that for the mail survey ($27.07). A significantly higher response rate was achieved among respondents randomly assigned to the mail (79.2%) than telephone survey (68.9%). Nonresponse bias was evident in both modes but, with the exception of age, was not differential between modes. The rate of missing responses was higher for mail than telephone respondents (1.59 vs. 0.49 missing items). Health ratings based on the SF-36 scales were less favorable, and reports of chronic conditions were more frequent, for mail than telephone respondents. Results are discussed in light of the trade-offs involved in choosing a survey methodology for health status assessment applications. Norms for mail and telephone versions of the SF-36 survey are provided for use in interpreting individual and group scores.

The MOS 36-Item Short-Form Health Survey (SF-36): Tests of Data Quality, Scaling Assumptions, and Reliability Across Diverse Patient Groups

Abstract: These findings support the use of the SF-36 survey across the diverse populations studied and identify population groups in which use of standardized health status measures may or may not be problematic.