A pilot study to test the effects of physical activity consultations on the physical activity levels and other health outcomes of people living with colorectal cancer and their partners

Feasibility will be measured by calculating the following rates:
1. Recruitment rate (number of participants randomised/number of eligible participants)
2. Completion rate (number of participants completing baseline and 6 month intervention assessments/number of participants randomised)
3. Adherence rate (number of physical activity consultations and telephone calls conducted/number of physical activity consultations and telephone calls scheduled)

1. Change in physical activity will be measured from baseline to 3 and 6 months follow-up in individuals living with colorectal cancer and their partner. Physical activity will be assessed for 7 consecutive days at each time-point using the Actigraph GT1M-Plus accelerometer (Actigraph LLC, Pensacola, Florida). Monitors will be attached to adjustable elastic belts and worn over the right hip under clothing during all waking hours. The raw accelerometry output (accelerometer count per minute [cpm], averaged over the monitoring period) will be used as a measure of total physical activity and will also be used to quantify the amount of monitored time spent in sedentary behaviour and moderate and vigorous physical activity using validated cut off points. Physical activity will also be assessed subjectively using the long (self-report) version of the International Physical Activity Questionnaire (IPAQ) to ascertain the types of activities participants engaged in as this information is not provided by the accelerometers. This questionnaire measures time spent in moderate and vigorous activity across four domains (work, transport, housework/gardening and leisure time) and time spent sitting in the previous 7 days.
2. Mental well-being will be measured at baseline, 3 and 6 months using the Hospital Anxiety and Depression (HADS) Scale (0 = Not at all, 4 = Most of the time). This is a brief, self-report questionnaire used to measure state anxiety and depression over the past week.
3. Quality of life in people living with colorectal cancer will be measured at baseline, 3 and 6 months using the Functional Assessment of Cancer Therapy C General (FACT-G) questionnaire. The latest version 4 is formulated into separate subscales: physical, emotional, social/family and functional well-being. The Functional Assessment of Cancer Therapy C Colorectal (FACT-C), which includes additional concerns for colorectal cancer patients, will also be used. Both scales questions are scored 0 = Not at all to 4 = Very much. Quality of life in partners will be measured by the WHOQOL-Bref instrument. The short form WHOQOL-Bref contains 26 items that have been extracted from the WHOQOL-100. It measures the following broad domains: physical health, psychological health, social relationships, and environment.
4. Body composition (i.e. fat and lean mass) will be measured at baseline, 3 and 6 months using a portable foot-to-foot bioelectrical impedance monitor (Tanita TBF-300 MA Body Composition Analyser, Harlow Printing Ltd, Tyne and Wear)
5. Predictors of change in physical activity: psychosocial constructs will be measured to test their predictive role for change in physical activity from baseline to 3 months and 6 months follow up in individuals living with colorectal cancer and their partners -
5.1. Perceptions of cancer risk in partners will be measured by a scale developed by Schwartz and colleague (Schwartz et al., 1995). The instrument has three items and uses a Likert scale ranging from 'much lower' to 'much higher' to generate a composite score.
5.2. Fear of cancer recurrence in individuals living with colorectal cancer will be measured using the Fear of Cancer Recurrence Inventory (Simard and Savard, 2009). The instrument has 42 items and uses a Likert scale to generate a composite score.
5.3. Key components of the revised theory of planner behaviour will be measured in individuals living with colorectal cancer and their partner using the following scales. Intention to exercise will be assessed on the mean of 2 items each measured on 7 point scales. Attitude will be assessed using the mean of 4 semantic differential scales, all scored -3 to +3 with higher scores indicating more positive attitudes towards exercising. Subjective norm will be assessed as the mean of 2 items, scored -3 to +3 with higher scores indicating stronger norms to exercise. Perceived behavourial control will be assessed as the mean of 3 items (scored 1 to 7), with higher scores indicating more control over exercising; past behaviour is well recognised as a strong predictor of future behaviour. This will be assessed as the mean of 2 items (scored 1 to 7), with higher scores indicating greater previous exercise; anticipated regret will be assessed by 2 items tapping inactivity regret that is anticipated regret about not exercising in the future, scored -3 to +3. The contributions of these predictor variables of attitude, subjective norm, perceived behavioural control etc in explaining the observed variance in, a) intention to exercise, and b) actual exercise behaviour 12 weeks and 6 months later will then be measured.
5.4. The quality of the relationship between the individual living with cancer and their partner will be measured to test if it affects adherence to the physical activity intervention or moderates any of the intervention effects. The validated relationship quality measures from the English Longitudinal Study of Ageing (Marmot et al., 2003) will be used, which assesses social support and is concerned with the quality of the respondent's social relationship with individual living with colorectal cancer or partner respectively. Specifically, respondents are asked about the presence of positive support from their partner (how much they understand the way the respondent feels about things, how much they can be relied on if the respondent has a serious problem and how much the respondent can open up to them to talk about worries); and about negative relations with each other (how much others criticise the respondent, how much they let the respondent down and how much they get on the respondent's nerves). Positive and negative support items are scored as 1 = not at all and 4 = a lot, such that higher numbers indicate more of each type of support. Three questions on the receipt of social support for physical activity in the previous week will also be included to assess whether the intervention changes received social support.