Ambulatory assessment data collection methods are increasingly used to study behavior, experiences, and patient-reported outcomes (PROs), such as emotions, cognitions, and symptoms in clinical samples. Data collected close in time at frequent and fixed intervals can assess PROs that are discrete or changing rapidly and provide information about temporal dynamics or mechanisms of change in clinical samples and individuals, but clinical researchers have not yet routinely and systematically investigated the reliability and validity of such measures or their potential added value over conventional measures. The present study provides a comprehensive, systematic evaluation of the psychometrics of several proximal intensive assessment (PIA) measures in a clinical sample and investigates whether PIA appears to assess meaningful differences in phenomena over time.
Data were collected on a variety of psychopathology constructs on handheld devices every 4 h for 7 days from 62 adults recently exposed to traumatic injury of themselves or a family member. Data were also collected on standard self-report measures of the same constructs at the time of enrollment, 1 week after enrollment, and 2 months after injury.
For all measure scores, results showed good internal consistency across items and within persons over time, provided evidence of convergent, divergent, and construct validity, and showed significant between- and within-subject variability.
Results indicate that PIA measures can provide valid measurement of psychopathology in a clinical sample. PIA may be useful to study mechanisms of change in clinical contexts, identify targets for change, and gauge treatment progress.