ABSTRACT
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.
Subject(s)
Accelerometry/standards , Exercise , Adult , Aged , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sedentary BehaviorABSTRACT
Aim: There is limited knowledge about the reaching of socioeconomic disadvantaged groups for prevention measures. Results of proactive contacting are presented for a 2-step cardiopreventive health examination programme (CHP) in 2 job centres in Northern Germany. Methods: The duration of the programme extended over a period of 10 weeks. All clients aged between 40 and 65 years were included. Phase 1consisted of a self-administered computer-based assessment, and if medical staff were present, blood pressure measurement and/or blood samples were taken. Participants without a history of cardiovascular diseases, interventional/surgical blood vessel procedures, diabetes and a body-mass-index ≤35 kg/m2 were invited to a specialised examination centre (phase 2). Logistic regression analysis was used to test predictors for participation in both phases. Variables were age, gender and for phase 2 the distance between participants' residence addresses and the address of the examination centre, cardiovascular risk factors, subjective health and socio-demographics. Results: 344 of the 1 049 invited job centre clients participated in the assessment. Women were more likely to participate than men. A number of 253 participants were invited for blood pressure measurement and blood sample taking. Participation of 209 persons was positively associated with age. A number of 138 participated in phase 2. Participation decreased with increasing distance between the participant's residence address and the address of the examination centre. Smokers, persons with less than 10 years of schooling and those who did not report an elevated level of blood lipids were less likely to participate. Conclusion: Blood pressure measurements and taking of blood samples in job centres were found to be highly accepted. The burden on potential participants to reach preventive measures should be minimised.
Subject(s)
Cardiovascular Diseases/prevention & control , Job Application , Mass Screening , Patient Selection , Vulnerable Populations , Adult , Cooperative Behavior , Female , Humans , Male , Middle Aged , Risk Assessment , Sex FactorsABSTRACT
There are reported two cases of nonprofessional skeletal fluorosis in senility. Causes of origin, clinical and roentgenological picture, histology and bone fluoride contents are specified, the findings discussed in connection with sodium fluoride therapy of osteoporosis.
