Table 1 Example items from each psychological construct scale, number of items and response scale, instrument development source(s), and reliability coefficients computed at each assessment point in this study.
| Psychological construct | Sample item |
Response scale (number of items) |
Construct source(s) [reference number] |
αT1 αT2 αT3 |
|---|---|---|---|---|
| self-efficacy |
In the next six months, I am confident that I can participate in regular physical activity:
When I have to do it by myself. |
"Not confident at all" to "Extremely confident" (9 items) | [43, 44] |
.93 .93 .94 |
| decisional balance pros |
Over the next 6 months:
Physical activity would help reduce tension or manage stress. |
"Not at all" to "Very much" (5 items) | [43, 44] |
.85 .83 .85 |
| decisional balance cons |
Over the next 6 months:
Physical activity would take too much time. |
"Not at all" to "Very much" (6 items) | [43, 44] |
.77 .75 .78 |
| behavioral processes |
How often in the past month:
Did you set physical activity goals for yourself that you could reach? |
"Never" to "Very often" (9 items) | [44] |
.86 .84 .87 |
| experiential processes |
How often in the past month:
Did warnings about health problems cause concern? |
"Never" to "Very often" (10 items) | [44] |
.81 .80 .82 |
| severity |
I feel:
For me, being physically inactive would be a very bad thing. |
"Definitely not" to "Definitely yes" (3 items) | [45, 46] |
.61 .60 .81 |
| vulnerability |
I feel:
If I don't get enough physically activity, I would be at risk for serious health problems. |
"Definitely not" to "Definitely yes" (3 items) | [45, 46] |
.84 .92 .91 |
| fear |
I feel:
Not getting enough physical activity would frighten me because of the possibility of developing serious health problems. |
"Definitely not" to "Definitely yes" (3 items) | [45, 46] |
.93 .94 .95 |
| response efficacy |
I feel:
For me, physical activity will keep me healthy. |
"Definitely not" to "Definitely yes" (3 items) | [45, 46] |
.83 .78 .91 |
| attitude |
For me regular physical activity over the next 6 months will be:
"Quite Useful" to "Quite Useless" | Response scale differed for each item (i.e., enjoyable, useful, wise, interesting, relaxing, beneficial) (6 items) | [47, 48] |
.78 .82 .80 |
| injunctive norms |
Over the next 6 months:
Most people in my social network want me to do regular physical activity. |
"Strongly disagree" to "Strongly agree" (4 items) | [47, 48] |
.67 .73 .73 |
| descriptive norms |
Over the next 6 months:
Most of my family members will participate in regular physical activity. |
"Strongly disagree" to "Strongly agree" (4 items) | [47, 48] |
.55 .61 .63 |
| social support |
Over the next 6 months:
People in my social network are likely to help me participate in regular physical activity. |
"Strongly disagree" to "Strongly agree" (3 items) | [47, 48] |
.76 .73 .73 |
| perceived behavioral control |
Over the next 6 months:
If I were really motivated participating in regular physical activity would be easy. |
Response scale differed for each item (4 items) | [47] |
.57 .60 .60 |