a mixed-method approach

Background Sedentary behaviours (SB) can be characterized by low energy expenditure in a reclining position (e.g., sitting) often associated with work and transport. Prolonged SB is associated with increased risk for chronic conditions, and due to technological advances, the working population is in office settings with high occupational exposure to SB. This study aims to assess SB among office workers, as well as barriers and strategies towards reducing SB in the work setting. Methods Using a mixed-methods approach guided by the socio-ecological framework, non-academic office workers from a professional school in a large public university were recruited. Of 180 eligible office workers, 40 enrolled and completed all assessments. Self- reported and objectively measured SB and activity levels were captured. Focus group discussion (FGD) were conducted to further understand perceptions, barriers, and strategies to reducing workplace SB. Environmental factors were systematically evaluated by trained research staff using an adapted version of the Checklist for Health Promotion Environments at Worksites (CHEW). Thematic analysis of FGD was conducted and descriptive analysis of quantitative data was performed. Results The sample was mostly Chinese (n = 33, 80 %) with a total of 24 (60 %) female participants. Most participants worked five days a week for about 9.5(0.5) hrs/day. Accelerometer data show that participants spend the majority of their days in sedentary activities both on workdays (76.9 %) and non-workdays (69.5 %). Self-report data confirm these findings with median sitting time of 420(180) minutes at work. From qualitative analyses, major barriers to reducing SB emerged, including the following themes: workplace social and cultural norms, personal factors, job scope, and physical building/office infrastructure. CHEW results confirm a lack of support from the physical infrastructure and information environment to reducing SB. Conclusions There is high SB among office workers in this sample. We identified multiple levels of influence for prolonged occupational SB, with a particular emphasis on workplace norms and infrastructure as important barriers to reducing SB and increasing PA. A larger, representative sample of the Singaporean population is needed to confirm our findings but it seems that any intervention aimed at reducing SB in the workplace should target individual, environmental, and organizational levels

Domain-Specific Adult Sedentary Behaviour Questionnaire (ASBQ) and the GPAQ Single-Item Question: A Reliability and Validity Study in an Asian Population

This study examined the validity and reliability of a domain-specific Adult Sedentary Behaviour Questionnaire (ASBQ) and the Global Physical Activity Questionnaire (GPAQ) single-item sitting question using self- and interviewer-administered modes of administration against the triaxial ActiGraph wGT3X-BT accelerometer. The ASBQ and the GPAQ were administered twice, seven days apart. Participants were asked to put on the waist-worn accelerometer for seven days. Convergent validity was assessed using Spearman’s rho, mean absolute error (MAE), and Bland-Altman analysis (n = 78). Reliability was assessed using the Spearman’s rho and intraclass correlation coefficient (ICC) (n = 84). Participants were adults aged 20–65 years and identifying as Chinese, Malay, or Indian. Only the self-administered GPAQ was significantly correlated with accelerometry-based measures (rho: 0.46), but not the interviewer-administered version (rho: 0.12). MAE for GPAQ was 207.5–218.3 min/day in relation to the accelerometer and for ASBQ was 154.7–174.6 min/day. Bland-Altman plots demonstrated large limits of agreement between questionnaire and accelerometry-based measures. While the self-administered GPAQ demonstrated a moderate correlation with accelerometry, the mean bias and the limits of agreement were large. The GPAQ (rho: 0.68–0.79; ICC: 0.68–0.78) and the ASBQ (rho: 0.53–0.64; ICC: 0.66–0.74) showed moderate-to-good reliability for total sedentary time using either self- or interviewer-administration. Future research should incorporate accelerometers to generate useful sedentary behaviour measures

Reliability and Validity of the Self- and Interviewer-Administered Versions of the Global Physical Activity Questionnaire (GPAQ).

The Global Physical Activity Questionnaire (GPAQ) was originally designed to be interviewer-administered by the World Health Organization in assessing physical activity. The main aim of this study was to compare the psychometric properties of a self-administered GPAQ with the original interviewer-administered approach. Additionally, this study explored whether using different accelerometry-based physical activity bout definitions might affect the questionnaire's validity.A total of 110 participants were recruited and randomly allocated to an interviewer- (n = 56) or a self-administered (n = 54) group for test-retest reliability, of which 108 participants who met the wear time criteria were included in the validity study. Reliability was assessed by administration of questionnaires twice with a one-week interval. Criterion validity was assessed by comparing against seven-day accelerometer measures. Two definitions for accelerometry-data scoring were employed: (1) total-min of activity, and (2) 10-min bout.Participants had similar baseline characteristics in both administration groups and no significant difference was found between the two formats in terms of validity (correlations between the GPAQ and accelerometer). For validity, the GPAQ demonstrated fair-to-moderate correlations for moderate-to-vigorous physical activity (MVPA) for self-administration (rs = 0.30) and interviewer-administration (rs = 0.46). Findings were similar when considering 10-min activity bouts in the accelerometer analysis for MVPA (rs = 0.29 vs. 0.42 for self vs. interviewer). Within each mode of administration, the strongest correlations were observed for vigorous-intensity activity. However, Bland-Altman plots illustrated bias toward overestimation for higher levels of MVPA, vigorous- and moderate-intensity activities, and underestimation for lower levels of these measures. Reliability for MVPA revealed moderate correlations (rs = 0.61 vs. 0.63 for self vs. interviewer).Our findings showed comparability between both self- and interviewer-administration modes of the GPAQ. The GPAQ in general but especially the self-administered version may offer a relatively inexpensive method for measuring physical activity of various types and at different domains. However, there may be bias in the GPAQ measurements depending on the overall physical activity. It is advisable to incorporate accelerometers in future studies, particularly when measuring different intensities of physical activity

Accelerometry-based physical activity summary estimates (median, IQR).

<p>^a Test of significance of difference between self- and interviewer-administered groups.</p><p>^b Valid wear time during waking hours.</p><p>Accelerometry-based physical activity summary estimates (median, IQR).</p

Proportion of participants according to the GPAQ classification of meeting recommended physical activity levels (low, moderate, high) by self- and interviewer-administered groups (n = 110).

<p>^a Classification according to the GPAQ guidelines.</p><p>Proportion of participants according to the GPAQ classification of meeting recommended physical activity levels (low, moderate, high) by self- and interviewer-administered groups (n = 110).</p

Spearman correlation between the GPAQ and accelerometry-based summary estimates of physical activity level (min/day), according to self- and interviewer-administered groups.

<p>Spearman correlation between the GPAQ and accelerometry-based summary estimates of physical activity level (min/day), according to self- and interviewer-administered groups.</p

Test-retest reliability of physical activity domains (min/day) by self- and interviewer-administered groups (n = 110).

<p>Median (IQR) of physical activity on average per day.</p><p>^a Significantly different <i>r</i>_<i>s</i> between self- and interviewer-administered groups.</p><p>^b Significantly different ICC between self- and interviewer-administered groups.</p><p>^c Not estimable due to lack of readings for vigorous activity.</p><p>Test-retest reliability of physical activity domains (min/day) by self- and interviewer-administered groups (n = 110).</p

Bland-Altman plots for the agreement of physical activity measurement (min/day) between the GPAQ and accelerometer.

<p>Comparisons of total-minute of activity versus a 10-minute bout definition at each of three intensities: MVPA, vigorous-, and moderate- intensity activities for the total sample (n = 108).</p