Table 3 Association between age and responses among patients in the test set. Values represent the coefficient and standard error generated from multivariable linear mixed effects models testing the association between age (per 20-year increase) and questionnaire responses after adjusting for postoperative day (plus cubic splines) with a nested random effect intercept varying among patients and among surgeries within each patient separately in those receiving additional descriptors and the test set of those receiving questionnaires without additional descriptors. The p-value is that for an interaction term between age and type of descriptor

From: A comparison of brief versus explicit descriptors for verbal rating scales: interrupted time series design