[Validation of the telephone call as a method for measuring compliance to arterial hypertension treatment in Extremadura].

Introduction: Pharmacological non-compliance is a significant problem that can affect patient health. The main aim of this investigation is to validate the telephone call to the patient' home as a self-report method of counting the amount of tablets taken by the patient, as an alternative method to a simple tablet count in the clinic (gold standard).

Patients And Methods: An observational, multicentre, prospective, and longitudinal study was conducted by 25 researchers in different health centres in Extremadura, and which included 125 consecutively enrolled patients with uncontrolled arterial hypertension, 121 ended the study. Three visits were made, including enrollment visit, follow-up visit at 4 weeks, and final visit at 8 weeks. A telephone call was made prior to the enrollment and final visit to remind the patients of the next visit, and to ask at the same time about the number of tablets remaining.

Results: A total of 121 patients completed the study. In the final visit, the phone-call method of compliance showed: 100% sensitivity, 86% specificity, 86.8% of overall accuracy, 30.4% PPV, 100% NPV, CP+ 7.13, CP- 0.0, and a kappa index of 0.415 (P<.0001). The area under the ROC curve was 0.995 (95% CI, 0.985-1).

Conclusions: It was concluded that the telephone phone call, as a therapeutic compliance method, can be a good alternative due to being almost universal, easy to use, its reduced cost, and without the need of patients to go to the medical centres.