Table 2 Subscales obtained after principal component analysis.

	Factor loadings
Subscale 1: Perceived necessity (α = 0.71; n = 78)
Q5. I have a clear picture of how cardiac rehabilitation will help the health of my heart	0.739
Q7. I have a clear picture of what I want to achieve by attending cardiac rehabilitation	0.698
Q1. Attending cardiac rehabilitation may help the long‐term recovery of my heart condition	0.677
Q6. Some aspects of the cardiac rehabilitation programme are unnecessary for me*	0.665
Q20. I hope that attending cardiac rehabilitation may help me to return to work more quickly	0.653
Subscale 2: concerns about exercise (α = 0.79; n = 96)
Q10. I am worried that some aspects such as exercise may be harmful to me	0.794
Q19. I am worried that I may not be able to keep up with the exercise part	0.748
Q17. I may not feel physically fit enough to attend cardiac rehabilitation	0.695
Subscale 3: practical barriers (α = 0.70; n = 75)
Q14. The cost of transport may prevent me from attending cardiac rehabilitation	0.855
Q13. Availability of transport will influence my decision to attend cardiac rehabilitation	0.718
Q22. It would be financially difficult to take time off work to attend cardiac rehabilitation	0.686
Subscale 4: perceived suitability (α = 0.74; n = 100)
Q24. Younger people are more likely to benefit from cardiac rehabilitation than an older, less active person	0.863
Q23. Cardiac rehabilitation is probably more suitable for people who have been previously active	0.770

*This item was reverse scored, hence factor loading is not negative.