Data were collected as part of a TNS Research International population-based omnibus
survey conducted in Great Britain between January and March 2014. Up to 4000 adults
per week are interviewed in Great Britain for the omnibus survey. The TNS omnibus
survey defines sample points using 2001 Census small-area statistics and the Postcode
Address File (stratified by social grade and Government Office Region) which are used
for random location sampling selection. Response rates are not recorded. However,
at each location, quotas are set for age, gender, children in the home and working
status to ensure a balanced sample. Survey respondents are verbally requested to volunteer
their participation in face-to-face interviews using computer-assisted personal interviewing
(CAPI). Three doors are left between each successful interview. NHS ethics approval
was obtained for this study (13/NW/0707).
Participants
Only respondents living in England who were aged 58–70 years and had no history of
CRC were included in the cancer screening section of the omnibus survey (n?=?1568).
Respondents aged 58–59 (n?=?187) were excluded from the present analysis because at
the time of the interview they were not yet eligible for CRC screening through the
English NHS BCSP. Therefore, all included respondents should all have been invited
for CRC screening through the organised national programme, irrespective of whether
they believed they had been invited or not. Responses to related questions were compared,
and cases were excluded if responses were logically inconsistent with each other (n?=?78;
e.g. responding ‘immediately decide not to do the test’ if receiving a test kit AND
‘will do the test’ when sent one). Respondents who had missing values (i.e. ‘refused’
or ‘don’t know’) for screening uptake (n?=?66) were also excluded. The exclusions
resulted in a final sample of 1237 respondents.
Measures
The term ‘bowel cancer’ was used throughout the survey, as it is commonly used to
refer to colorectal cancer in the United Kingdom.
Micro actions
Respondents were informed at the beginning of the survey that the subsequent part
would consist of questions about bowel cancer screening and the home-based stool test,
which is offered through the NHS BCSP. They were shown images of the invitation letter,
the information booklet, the instruction leaflet and the screening test kit to ensure
they recalled the test. They were then asked the open-ended question:
‘We are interested in what people do, or would do, when they are sent the screening
test kit. Imagine you are at home and you have just opened an envelope in which you
find a test kit and a leaflet with instructions of how to complete the test. Of course,
you would usually need to wait until you have a bowel motion before you can complete
the kit. By bowel motion we mean “to go for a pooâ€. What would you do after you receive
the test kit through the post?’
Pilot interviews (n?=?8) had been conducted earlier to develop predefined answer categories.
These categories were then tested in a pilot online survey (n?=?427), in which respondents
were shown all the answer categories as well as having the option to give a verbatim
response.
In contrast to the pilot survey, respondents in the present study gave open replies
to the interviewers. Responses were coded by the interviewers using answer categories
that were not shown to the respondents. Verbatim responses were recorded if interviewers
were unsure or if the answer did not fit into any of the codes. Interviewers were
instructed to collect as much information as possible and use multiple codes as appropriate:
Immediately decide not to do the test/ throw the kit away [excluded from analysis]
Immediately decide to do the test/ do the test [excluded from analysis]
Decide (whether or not to do) the test after some thought
Put (the kit) aside to deal with later
Put on my’things to do list/ pile’
Verify source of information
Read the instruction leaflet
Discuss it with a health care professional
Discuss it with my partner/family/friend
Decide when to do the test
Make a note somewhere (e.g. diary, post-it, calendar to remind myself)
Put the kit near the toilet (so that I have it ready when I have a bowel motion)
Other, namely… [verbatim response]
Since the research aim was to examine micro actions that are potentially undertaken
between receiving the test kit and (non-) completion of the test kit, responses referring
to screening intention and the actual behaviour were excluded. As a result, the response
categories ‘immediately (decide) to do the test’ and ‘immediately decide not to do
the test’ were not further analysed. Intention formation (e.g. ‘decide whether or
not to do the test after some thought’), however, was considered a micro action. Verbatim
responses (n?=?48) were coded by two independent coders (SHL and CV), with 82Â % agreement
and a kappa inter-rater agreement of 0.78, suggesting there was substantial inter-rater
agreement 18], 19]. Coding disagreements were resolved through discussion. Most ‘other’ responses were
recoded under the existing answer categories. Two new categories were created following
the coding process: ‘unclear’ (n?=?11) and ‘other micro action’ (n?=?6). Due to the
small number of cases, these newly created categories were not included in the analysis.
For each micro action, a dichotomous variable was created to indicate either that
a respondent had mentioned the micro action (1) or not (0). Respondents who had not
mentioned any micro actions had a score of (0) for all micro actions but were retained
in the analysis.
Past screening uptake
Respondents were then asked if they had ever been invited to do a stool test for the
National Health Service (NHS) Bowel Cancer Screening Programme (BCSP). If their answer
was affirmative, they were asked further questions to determine the number of times
they had been invited and the number of times they had participated in the screening
programme. A dichotomous variable for past ever screening uptake was created with
the categories non-responders (never invited or never completed) and responders (?1
test kits completed).
Screening intention
Respondents were asked ‘Do you think you will do the stool test when you are (next)
sent one?’ on a five-point scale (no, definitely not 1]/no, probably not 2]/not sure 3]/yes, probably 4]/yes, definitely 5]/not applicable [missing]). Screening intention was included as a control variable
in a multivariable regression analysis.
Sociodemographics
Sex, age, marital status (married/ widowed, divorced or separated/ single), ethnicity
(white/ non-white) and social grade were recorded to describe the sample. The National
Readership Survey social grade classification system based on occupation (or previous
occupation if retired) was used as a measure of social grade: AB (managerial/ professional);
C1 (supervisory); C2 (skilled manual), DE (semi-skilled/ unskilled manual, state pensioners,
casual/ lowest grade workers or unemployed). For people who were not working, the
chief wage earner in the household’s occupational status was used.
Data analysis
Descriptive statistics were first given for each micro action and each micro action
by past screening uptake. Correlations between micro actions were also examined. Simple
logistic regression analysis was then used to examine bivariate associations between
past uptake and endorsement of each micro action. Micro actions that showed a statistically
significant association at the .05 level and screening intention were included in
multivariable logistic regression analyses. All analyses used pairwise deletion and
were conducted with Stata Version 13SE 20].