Conclusions
Engagement, perceived usefulness, and satisfaction of the overall program were good. Engagement and acceptability of the tailored advice specifically were good despite the main outcomes paper reporting no physical activity changes observed in the tailored advice only participants. Participants explained that they wanted further personalisation of the tailored advice and/or personal contact. Fitbit integration did not improve the engagement or acceptability of the tailored advice, however participants engaged with and felt as though they benefited from using a Fitbit device. Usability ratings of the website were modest but highest in the Fitbit + tailored advice group. The action planning tool and exercise plans had a low engagement and perceived usefulness, and many participants felt as though the exercise plans were not well tailored to their abilities. Future web-based behaviour change interventions for older adults should ensure advice and exercise plans are well tailored to participants’ abilities, age and situation, consider including personal contact, better integrate activity tracker data with other intervention components, and ensure adequate website usability testing with the target group.