Ecological momentary assessment (EMA) is a reliable and valid method to broadly sample multiple functioning domains in schizophrenia, according to a study published in Schizophrenia Bulletin.
To examine the feasibility, reliability, and validity for EMA of functioning behaviors in schizophrenia, investigators recruited individuals aged 18 to 65 years who met the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition diagnostic criteria for schizophrenia (n=82) or schizoaffective disorder (n=18). Age-matched controls had no diagnoses of past or current mood, anxiety, or psychotic disorders (n=71).
Participants were provided with smartphones to deliver EMA surveys at random intervals 7 times per day for 7 days. Surveys were predominantly composed of check-box questions about the time spent at home and functioning behaviors performed during the previous hour, including self-care, work or school, home care, and at-home and outside-home leisure, as well as a number of questions about social interactions and social context. A second test–retest reliability follow-up assessment was offered to participants 4 weeks after the initial week of EMA sampling, until approximately 75 patients and 50 controls were reassessed. In-lab functioning measures included the specific levels of functioning patient and informant report forms (SLOF-P, SLOF-I) and the self-report version of the Independent Living Skills Survey (ILSS).
Adherence was high, with 42 out of 49 programmed surveys completed on average, and the 2 groups did not differ significantly in this regard. The schizophrenia group reported spending more time at home during the previous hour than the controls (controls: M=32.4 minutes [standard deviation=15.2] vs schizophrenia group: M=43.1 minutes [SD=10.6]; t(169)=5.42; P <.001; d=0.8), and being at home the entire previous hour on a significantly greater proportion of surveys (controls: M=46% [SD=25%] vs schizophrenia group: M=62% [SD=20%]; t(169)=4.71; P <.001; d=0.7). When leaving the home, controls transported themselves independently more often (controls: M=65% [SD=29%] vs schizophrenia group: M=45% [SD=32%]; t(164)=4.06; P <.001; d=0.65). Significant but modest correlations were found between EMA and the ILSS, but not the SLOF-P or SLOF-I total scores.
Limitations of this study include validation of EMA reports relative to in-lab assessments and functioning milestones, but not convergent validity relative to video, diary, or phone recall interviews. There was possible sampling bias toward recruiting lower functioning controls, mostly unemployed individuals who may have been more likely to be at home more of the day.
The researchers demonstrated excellent feasibility and validity of EMA as a measure of real-world functioning and support the use of EMA as an outcome measure of functioning with sensitivity for use in clinical trials. “We need to use EMA to determine whether interventions improve what people actually do in the real world and to better understand the determinants of actual participation rather than potential,” the researchers concluded. “In a future paper, we will report on some of the determinants (eg, neurocognition, mood, motivation, defeatist beliefs) of EMA measures of actual participation.”
Granholm E, Holden JL, Mikhael T, et al. What do people with schizophrenia do all day? Ecological momentary assessment of real-world functioning in schizophrenia [published online August 23, 2019]. Schizophr Bull. doi: 10.1093/schbul/sbz070