en Cardiology Cardiology Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:14pt"><b><i><span style="color:blue">Background</span></i></b><i><span style="color:blue">:</span></i> Recognizing thirst distress and sodium intake restriction using valid and reliable tools enable evidence-based care, and improve treatment outcomes for the elderly with heart failure (HF). The present study investigated the psychometric properties of the thirst distress scale (TDS-HF) and dietary sodium restriction questionnaire for Iranian&#39;s elderly with HF (DSRQ-HF).</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Methods:</span></i></b> This crossectional study was conducted during 2021-2022. Two hundred and forty elderly people referring to the cardiology clinics and offices in the western region of Mazandaran, Iran were selected by the convenient sampling method. First, the two questionnaires were translated. Then, face, content, and construct validity were assessed. Several indices were used to evaluate, including the chi-square/degree-of-freedom ratio (CMIN/DF), parsimonious normed fit index (PNFI), comparative fit index (CFI), parsimonious comparative fit index (PCFI).</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Results:</span></i></b> The value of content validity index of all items of the two questionnaires was higher than 0.62. The fit indices, including PCFI=0.594, PNFI=0.582, CMIN/DF=1.987, and CFI=0.979, confirmed the one-factor construct of TDS. PCFI=0.724, PNFI=0.661, CMIN/DF=1.935, ad CFI=0.905, indicated the confirmation of the three-factor construct of DSRQ. The value of Cronbach&#39;s alpha of the two questionnaires were 0.86<span dir="RTL" lang="FA">.</span> The value of &Omega; of the TDS-HF and DSRQ-HF were 0.858, and 0.860, respectively. The value of &theta; of the TDS-HF and DSRQ-HF were 0.858, and 0.861, representing the suitability of both constructs.</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Conclusion</span></i></b><i><span style="color:blue">:</span></i> The TDS-HF and DSRQ-HF can be used to measure the psychometric effects of diet therapy and behaviors of the elderly with HF in relation to adherence to diet therapy.</span></span></span><br> &nbsp; Thirst distress, Dietary sodium restriction, Heart failure, Elderly, Questionnaire, Validation 484 493 http://caspjim.com/browse.php?a_code=A-10-459-3&slc_lang=en&sid=1 Khatereh Aminin khatereh.m.amini98@gmail.com 100319475328460049003 100319475328460049003 No Student Research Committee, Nursing Care Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Fatemeh Ghaffari fatemehghaffari@yahoo.com 100319475328460049004 100319475328460049004 No Nursing Care Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Ali Pourhabib 100319475328460049005 100319475328460049005 No Nursing Care Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Zahra Fotokian zfotoukian@yahoo.com 100319475328460049006 100319475328460049006 Yes Nursing Care Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran Mohammad hassan Nadimi zfotoukian@gmail.com 100319475328460049007 100319475328460049007 No Department of Cardiology, Ramsar International Campus, Mazandaran University of Medical Sciences, Sari, Iran