An implementation intentions intervention to increase uptake of mammography

This study tested an implementation intentions intervention to increase uptake in the United Kingdom's National Health Service Breast Screening Programme. The intervention asked women to plan how they would overcome up to 3 previously identified barriers to attending.

In a randomized controlled trial, 2,082 participants were allocated to an intervention condition, an assessment-only condition, or a nonassessment control condition. The intervention condition was designed to help women plan how to change their appointment, how to arrange transport, and how to negotiate time off work. The assessment-only condition controlled for the possibility that completing a questionnaire about mammography might in itself influence attendance, and the nonassessment condition was a control against any effect on attendance that mere contact with the research team might have.

Mean age of respondents was 56.1 years, and 99.4% were White British. In the full intention-to-treat analysis, which included all participants, attendance was found to be almost identical across the 3 conditions, around 80%. Some of the women in the intervention condition, however, failed to write their plans on the questionnaire (10.6% for changing the appointment, 2.1% for travel arrangements, and 21.1% for taking time off work) or said that planning was irrelevant to them (2.4% for changing the appointment, 1.7% for travel arrangements, and 32.4% for taking time off work). A second analysis, of planning time off work, therefore, examined the 620 respondents in the intervention condition more closely and found that those who planned were significantly more likely to attend than those who did not. A 3rd analysis, excluding the 209 respondents for whom planning time off work was irrelevant, revealed that the most likely to plan were those whose initial intentions to attend were strong but whose perceptions of control over making the necessary arrangements to attend were weak.

Two main implications of the findings are discussed: the importance of planning in implementation intentions interventions and the validity of the theoretical distinction between motivation and volition.