This case-control study was conducted on 139 hemodialysis patients who visited a referral teaching hospital in Mazandaran province, Iran, between 2020 and 2021. The inclusion criteria were individuals over the age of 18, physical ability to answer questionnaires, and informed consent. The exclusion criteria were incurable diseases, patient non-cooperation, non-consent, and severe psychiatric disorders. As there was no data on the mean (SD) of the Health Promoting Lifestyle Profile in two groups of participants in the previous study, we used a previous study that assessed depression and anxiety in hemodialysis patients (
19). Also, we calculated the sample size of the participants based on the Health Promoting Lifestyle Profile of the patients on a pilot study at the beginning of the study with the following formula:
Where I ±= 0.5; = 0.20; S = 13; d = 4.5
After inserting the equation, the minimum number of necessary samples was determined to be 139 patients undergoing hemodialysis at Shahid Beheshti Hospital in Babol City. Also, 139 healthy individuals were included in the study using the convenience sampling method.
In this study, the project manager (a medical student) invited patients who met the inclusion criteria and were visiting the dialysis unit to participate. During an interview session with the patients waiting for hemodialysis, the researcher checked their inclusion criteria and invited them to participate if they were eligible. The patient's demographic information was collected after obtaining their consent and completing the informed consent forms. To prevent fatigue in patients and increase the accuracy of data collection, the questionnaires were completed in two consecutive dialysis sessions. In the first session, the Hospital Anxiety Depression Scale (HADS) (14 questions) and the Coronavirus Anxiety Scale (CAS) (18 questions) were completed after an interview to obtain their personal information. In the second session, the Health Promoting Lifestyle Profile II (HPLPII) questionnaire (52 questions) was completed.
For the control group, the researcher went to the nephrology clinic of the same hospital and examined those who were homogeneous with the case group in terms of gender, age, education level, and important underlying diseases (e.g., diabetes, hypertension, hyperlipidemia, and thyroid diseases). Individuals who met the inclusion criteria were invited to participate. The data collection tools for the control group included the HPLPII questionnaire, the HADS, and the CAS.
The HPLPII questionnaire consisted of 52 questions designed by Walker in 1990. This questionnaire measures health responsibility, nutrition, physical activity, stress management, and interpersonal relations on a 4-point Likert scale: "never = 1, sometimes = 2, often = 3, and always = 4". Walker et al. (1990) confirmed the reliability of the lifestyle questionnaire as 0.86, 0.86, 0.8, 0.85, 0.79, and 0.87 for the six scales and 0.94 for the entire questionnaire using Cronbach's alpha (
20). The validity and reliability of the questionnaire were also confirmed in Iranian studies. Confirming the construct validity, Pourmidani et al. reported the correlation between the subscales of this questionnaire between 0.67 and 0.80, and Mohammadi Zeidi et al. reported between 0.27 and 0.86. Also, the content validity of this tool has been qualitatively confirmed by Fathi Ashtiani and Jafari Kandovan (
21-
23). The reliability of this questionnaire has been confirmed in Iranian studies. In Mohammadi Zeidi et al.'s study, the Cronbach's alpha coefficient of the questionnaire for the whole tool was 0.82, and its dimensions were between 0.64 and 0.91, and in Fathi Ashtiani and Jafari Kandovan's study, it was 0.96. mentioned (
22,
23).
The HADS was utilized as a tool in this research. This scale was first introduced by Zigmond and Snaith in 1983 as a method for screening psychiatric disorders in public outpatient clinics. The HADS measures depression and anxiety in outpatients simultaneously. The internal consistency of this measurement subscale was indicated by the measurement of Cronbach's alpha for the seven items of the depression subscale (Alpha = 0.70) and seven items of the anxiety subscale (
24). Each question on this scale is scored from 0 to 3; hence, the scores of the depression and anxiety subscales range from 0 to 21 in the HADS. Higher scores indicate higher anxiety and depression. The validity of this questionnaire has been confirmed in Iranian studies. In Montazeri's study, assessing the validity by comparing the known groups showed satisfactory results. Both anxiety and depression subscales discriminated well between subgroups of patients who differed in clinical status (
25). The face and content validity of the questionnaire has been confirmed by Kaviani et al. (
24). The reliability of this questionnaire has been confirmed in Iranian studies. Amini et al. reported 0.866 and 0.735 coefficients, Montazeri et al. calculated 0.78 and 0.86 coefficients, and Kaviani obtained 0.85 and 0.70 coefficients for Cronbach's alpha of anxiety and depression subscales (
24-
26).
The CAS was another data collection tool used in the present study. Among Iranian researchers, Alipour et al. designed this scale in 2020, and it is scored on a 4-point Likert scale (never = 0, sometimes = 1, often = 2, and always = 3). The minimum and maximum scores for this tool are 0 and 54, respectively. A higher score indicates higher anxiety. The face and content validity of this tool was confirmed qualitatively. The reliability of this tool is 0.879 for the first dimension (psychological), 0.861 for the second dimension (physical), and 0.919 for the entire tool, using Cronbach's alpha method (
27).
We used SPSS22 software for data analysis. Descriptive results were displayed in a table (absolute and relative frequency). The Kolmogorov-Smirnov test was utilized to examine the normality of data distribution. All variables in the results had P > 0.05, indicating the normality of data distribution. Therefore, parametric tests were used for data analysis. The t-tests were utilized to examine the differences in the total mean scores and different scopes of the questionnaires.
The present study was approved by the Ethics Committee of Babol University of Medical Sciences, with the code IR.MUBABOL.REC.1399.296. The researchers explained the purpose of the research to the participants, and they signed informed consent forms. The researchers committed themselves to observing the ethical principles of the Declaration of Helsinki. They guaranteed that the patient's personal information would remain confidential. The researchers also ensured that participation in the study was voluntary and would not affect the patient's care and treatment process. The participants had the right to leave the study. The researchers sought to comply with the principles of the Committee on Publication Ethics (COPE).