Purpose: Guidelines recommend that treatment decisions for nonvalvular atrial fibrillation (NVAF) incorporate patient preferences. We designed a multicomponent decision tool to inform patients of their individual risks of stroke and bleed over a meaningful time period (5 years), assist patients in clarifying their priorities, and to facilitate patient-physician communication.
Methods: We conducted a pilot, clustered randomized controlled trial, in which patients assigned to one group of providers completed the decision tool before seeing their primary care physician and patients assigned to a second group received usual care. Data were collected pre- and post visit to assess outcomes. Visits were audiotaped. The primary outcome variables were the Informed and Values Clarity subscales of the low-literacy version of the Decisional Conflict Scale 6. Secondary outcomes were: knowledge, anxiety, worry, rationale for preferred treatment, and discussion of NVAF-related outcomes. Between group differences were measured using a linear regression model which included sociodemographic characteristics, quality of life, and baseline scores. A sample size of 135 was calculated assuming, Type 1 error of 0.05, power of 0.80, two-tailed, an effect size (Cohen's d) of 0.5 after inflating the initial estimate by 5% for possible missing values.
Results: 69 patients were enrolled in the intervention group and 66 in the control group. Participants in the intervention group had lower scores on the Informed [11.9 (-21.1, -2.7)] and Values Clarity subscales [-14.6 (-22.6, -6.6)]. Participants in the intervention group were more likely to be able to name the medications for reducing stroke risk (61% vs 31%, p<0.001) and to know their side effects (49% vs 37%, p=0.07), although the latter did not reach statistical significance. The risk of stroke was discussed more frequently in the intervention than control group (71% vs 12%, p<0.0001), as was the risk of bleed (71% vs 21%, p<0.0001). Between groups differences for remaining outcomes are presented in the table.
Conclusion: The tool was effective at improving perceived knowledge and value clarity and at increasing physician-patient communication.
Intervention (mean) | Control (mean) | Difference (95% CI) | P-Value | |
| Accuracy: stroke risk | 9.1 | 14.2 | -5.2 (-1.9, -8.4) | <.001 |
| Accuracy: bleeding risk | 8.7 | 13.1 | -4.4 (1.4, -7.5) | <.001 |
| Anxiety | 13.0 | 13.4 | -0.38 (-1.4, .67) | 0.46 |
| Worry: stroke risk | 1.8 | 1.6 | 0.18 (-0.31, .66) | 0.47 |
| Worry: bleeding risk | 1.5 | 1.9 | -0.43 (-1.1, .29) | 0.24 |
See more of: The 33rd Annual Meeting of the Society for Medical Decision Making