The End-Stage Renal Disease-Adherence Questionnaire (ESRD-AQ) for patients requiring in-center HD was designed to measure treatment adherence behaviors in four dimensions: HD attendance, medication use, fluid restrictions, and diet recommendations. Items were initially generated based on in-depth literature reviews and in consultation with clinical experts, such as nephrologists and nephrology researchers, HD nurses, and renal dieticians. The final version of the ESRD-AQ consists of 46 questions/items divided into five sections (see Table 1 ). The first section pursues general information about patients' ESRD and RRT-related history (5 items), and the remaining four sections ask about treatment adherence to HD treatment (14 items), medications (9 items), fluid restrictions (10 items), and diet recommendations (8 items). These four final sections directly measure adherence behaviors (14, 17, 18, 26, 31, and 46), and patients' knowledge and perceptions about treatment (11, 12, 22, 23, 32, 33, 41, and 42). Responses to the ESRD-AQ utilize a combination of Likert scales and multiple choice, as well as “yes/no” answer format.
The adherence behavior subscale is scored by summing the responses to questions 14, 17, 18, 26, and 46. The weighting system for scores was determined based on the degree of importance relevant to clinical outcome of each dimension. For example, missing or shortening HD has been reported to have a stronger association with mortality of patients with ESRD than other components of adherence behavior; therefore, it was given more weight in computing the adherence scores (Leggat et al., 1998 (link); Saran et al., 2003 (link)). In addition, the ESRD-AQ adjusts scores for question numbers 14 (“During the last month, how many complete dialysis treatments did you miss?”), 18 (“During the last month, when your dialysis treatment was shortened, what was the average numbers of minutes?”), and 26 (“During the past week, how often have you missed your prescribed medicines?”), depending on the reasons for not adhering. For example, patients with medical reasons for missing or shortening the HD treatment (such as having HD access problems or physical symptoms during HD) obtained a full score (seeTable 2 ).
The attitude/perception subscale is scored by summing the responses to questions 11, 12, 22, 23, 32, 33, 41, and 42. The remaining questions obtain information about patients' ESRD and RRT related history. The ESRD-AQ is designed such that higher scores indicate better adherence.
The adherence behavior subscale is scored by summing the responses to questions 14, 17, 18, 26, and 46. The weighting system for scores was determined based on the degree of importance relevant to clinical outcome of each dimension. For example, missing or shortening HD has been reported to have a stronger association with mortality of patients with ESRD than other components of adherence behavior; therefore, it was given more weight in computing the adherence scores (Leggat et al., 1998 (link); Saran et al., 2003 (link)). In addition, the ESRD-AQ adjusts scores for question numbers 14 (“During the last month, how many complete dialysis treatments did you miss?”), 18 (“During the last month, when your dialysis treatment was shortened, what was the average numbers of minutes?”), and 26 (“During the past week, how often have you missed your prescribed medicines?”), depending on the reasons for not adhering. For example, patients with medical reasons for missing or shortening the HD treatment (such as having HD access problems or physical symptoms during HD) obtained a full score (see
The attitude/perception subscale is scored by summing the responses to questions 11, 12, 22, 23, 32, 33, 41, and 42. The remaining questions obtain information about patients' ESRD and RRT related history. The ESRD-AQ is designed such that higher scores indicate better adherence.
