When a behavior is monitored, it is likely to change, even if no change may be intended. This phenomenon is known as measurement reactivity. We investigated systematic changes in accelerometer-based measures over the days of monitoring as an indicator of measurement reactivity in an adult population. One hundred seventy-one participants from the general population (65% women; mean age = 55 years, range: 42-65 years) wore accelerometers for 7 consecutive days to measure sedentary behavior and physical activity (PA). Latent growth models were used (a) to investigate changes in accelerometer wear time over the measurement days and (b) to identify measurement reactivity indicated by systematic changes in sedentary time (ST), light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA). Over the measurement days, participants reduced accelerometer wear time by trend (rate of change [b] = -4.7 min/d, P = .051, Cohen's d = .38), increased ST (b = 2.4 min/d, P = .018, d = .39), and reduced LPA (b = -2.4 min/d, P = .015, d = .38). Participants did not significantly reduce MVPA (P = .537). Our data indicated that accelerometry might generate reactivity. Small effects on ST and LPA were found. Thus, the validity of accelerometer-based data on ST and LPA may be compromised. Systematic changes observed in accelerometer wear time may further bias accelerometer-based measures. MVPA seems to be less altered due to the presence of an accelerometer.

BackgroundSchizophrenia and bipolar disorder are characterized by a high disease burden. Antipsychotic medication is an essential part of the treatment. However, non-adherence is a major problem. Our aim was to examine potential determinants of non-adherence for patients with severe mental disorders.MethodsBaseline data of the study “Post stationary telemedical care of patients with severe psychiatric disorders” (Tecla) were used. Medication adherence was assessed with the Medication Adherence Report Scale German version (MARS-D). A logistic regression was calculated with age, sex, education, employment status, level of global functioning, social support and intake of typical and atypical antipsychotics as predictors.ResultsN = 127 participants were included in the analysis (n = 73 men, mean age 42 years). The mean MARS-D Score was 23.4 (SD 2.5). The most common reason for non-adherence was forgetting to take the medicine. Significant positive determinants for adherence were older age (OR 1.02, 95% CI 1.011–1.024, p < 0.0001), being employed (OR 2.46, 95% CI 1.893–3.206, p < 0.0001), higher level of global functioning (overall measure of how patients are doing) (OR 1.02, 95% CI 1.012–1.028, p < 0.0001), having social support (OR 1.02, 95% CI 1.013–1.026, p < 0.0001), and intake of typical antipsychotics (OR 2.389, 95% CI 1.796–3.178, p < 0.0001). A negative determinant was (female) sex (OR 0.73, 95% CI 0.625–0.859, p = 0.0001).ConclusionsEspecially employment, functioning and social support could be promising targets to facilitate adherence in patients with schizophrenia or bipolar disorder.Trial registrationThis study is retrospectively registered at the German Clinical Trials Register with the trial registration number DRKS00008548 at 21/05/2015.

Post-operative CI after AAA repair is not common but is associated with worse in hospital outcomes and lower long-term survival. EVAR was protective after both rAAA and iAAA repairs. When discussing the treatment of AAA with patients the protective effect of EVAR should be considered. Future studies should validate predictive scores and advance preventive strategies.