The effect of different sampling and recall periods in the CAHPS Clinician & Group (CG-CAHPS) survey

Objective: To examine the effect of changing the sampling and reference periods for the CAHPS^® Clinician & Group Survey from 12 to 6 months. Data Sources/Study Setting: Adult patients with a visit in the last 12 months to New England community health centers. Study Design: We randomly assigned patients to receive a survey with either a 12- or 6-month recall period. Data Collection/Extraction Methods: Questionnaires were mailed to patients, with a second questionnaire mailed to nonrespondents, followed by six attempts to complete a telephone interview. Principal Findings: If the sampling criterion was a visit in the last 6 months, 9 percent of those with a visit in the last 12 months would not have been surveyed. A total of 1837 patients completed 6-month surveys (44.9 percent response rate); 588 completed 12-month surveys (46.0 percent response rate). Shortening the reference from 12 to 6 months reduced the proportion of respondents reporting a blood test, X-ray, or other tests. Adjusting for respondent characteristics, the most positive response was selected more often on the 6-month survey for 12 out of 13 questions, and three of these differences were statistically significant (P < 0.05). Conclusions: Surveys using a 6-month recall period may yield slightly higher scores than surveys with a 12-month recall period.