GEE analyses were also used to explore changes in participants’ symptom levels as measured by the PHQ-9 and GAD-7 over time (Karin et al., 2018). All GEE models specified a gamma distribution with a log link response scale to address positive skewness in the dependent variable distributions...
Placebo effects are mediated by expectancies6—since symptom changes can be positive or negative (as in nocebo effects), these can more generally be termed “expectancy effects”. Unless a treatment is not perceived7, expectancy effects are implicated ineverytreatment, regardless of whether it involv...