Contracting with outpatient hemodialysis patients to improve adherence to treatment.

The purpose of this study was to examine the relationship between contingency contracting and adherence to prescribed therapy in outpatient chronic hemodialysis patients. A quasi-experimental, pretest/posttest design was used. The sample included 15 hemodialysis patients, 6 in the phosphorus group and 9 in the weight-gain group. The study was conducted at an outpatient hemodialysis center in a Midwestern rural state. Specific variables investigated were interdialytic weight gains and serum phosphorus levels that reflect adherence to fluid restrictions and to taking phosphate-binding medications. Weekly interviews were conducted with each patient and content analysis of interview data was completed to identify categories related to adherence and nonadherence. Pre- and postcontract weight gains and phosphorus levels were analyzed with a paired two sample t-test. The categories related to adherence and nonadherence included physiological, psychological, environmental, locus of control/self-control/self-praise, economical, medical, knowledge deficit, health benefits, family support, and social support. Adherence to taking phosphate-binding medication responded more favorably to contingency contracting than did adherence to fluid restrictions. Chronic outpatient hemodialysis patients in the sample responded to the use of contingency contracting and developed techniques to remember to take phosphate-binding medications in order to lower serum phosphorus medications.