Assessment of macular findings by OCT angiography in patients without clinical signs of diabetic retinopathy: radiomics features for early screening of diabetic retinopathy.

This cross-sectional study aimed to quantitatively analyze the optical coherence tomography angiography (OCTA) images using MATLAB-based software and evaluate the initial changes in macular vascular density and the distortion of the foveal avascular zone (FAZ), before the clinical appearance of diabetic retinopathy. For this purpose, 21 diabetic patients without any clinical features indicating DR, and 21 healthy individuals matched with patients based on their demographic characteristics were included. Macular thickness, macular vascular density, and morphological changes of FAZ were assessed using OCTA. The diagnostic ability of morphological parameters was evaluated by receiver operating curve analysis. The intraclass correlation coefficient (ICCC) index was used to check the consistency of the extracted values. There was no significant difference in age, gender, LogMAR visual acuity, spherical equivalent, and intra-ocular pressure amongst patients and controls. No correlation was found between age and the FAZ area as well as vascular density. The vascular structure of the superficial layer showed FAZ enlargement, reduced vascular density in the macular area, and significant deviations of FAZ shape parameters (convexity and Frequency Domain Irregularity) in patients compared with healthy individuals. Measurements were highly correlated between separate imaging sessions with ICCC of over 0.85 for all parameters. The represented data suggests that radiomics parameters can be applied as both an early screening tool and guidance for better follow-up of diabetic patients who have not had any sign of DR in fundoscopic exams.

Investigating the impact of modified mindfulness-based stress reduction (MBSR) program on occupational burnout and other mental health status among nonmedical staff in a hospital: a randomized controlled trial.

OBJECTIVE: Burnout is a prolonged psychological response to a longstanding interpersonal stressor at work. It can progress to other mental illnesses, such as anxiety and depression. In today's society, burnout has become widespread, and it is currently a serious challenge in health systems. This study intended to investigate the impact of mindfulness training on burnout and depression, anxiety, and stress of nonmedical staff in a hospital in Shiraz-Iran. METHOD: Fifty nonmedical staff in a Shiraz-Iran hospital were enrolled in this two groups' randomized controlled trial. The intervention group was trained by a modified mindfulness-based stress reduction (MBSR) program, and the control group received no intervention. The outcome was assessed by the Copenhagen burnout inventory (CBI) and DASS-21 questionnaire on three occasions including before T0, immediately after T1, and 3 months after the intervention T2. RESULTS: Comparing the score changes between intervention and control groups showed that the reduction of work­distaste­related burnout, client­related burnout, anxiety, and stress scores in the intervention group was significantly more than in the control group in the time interval from T0 to T1. The scores in the intervention group in three subscales of CBI, including work­characteristic­related burnout, work­distaste­related burnout, and client­related burnout, decreased significantly immediately after the training (T1) compared to before (T0). Also, the scores did not change significantly after 3 months following training. CONCLUSIONS: Mindfulness training can be used as an effective way to improve occupational burnout, anxiety, and stress in occupations other than health professionals. Its effect is stable for at least a few months. It is recommended that future studies focus on investigating the feasible way to integrate this training into the working environment. Forthcoming studies should also determine whether the impact of this intervention will last longer and find possible ways to extend its influence.

Evaluating the effects of dark chocolate formulated with micro-encapsulated fermented garlic extract on cardio-metabolic indices in hypertensive patients: A crossover, triple-blind placebo-controlled randomized clinical trial.

This study aimed to investigate the health-related effects of microencapsulated fermented garlic extract (FGE) containing dark chocolate in hypertensive adults. For this purpose, 36 hypertensive adults (15 males vs. 21 females) were randomized to receive the FGE (5 g/day) dark chocolate containing 650 mg of FGE powder or the placebo. Intervention periods lasted for 6 weeks and were separated by a 3-week wash-out period. The response variables included blood pressure, anthropometric indices, lipid profile, and inflammatory and oxidative stress indices. Statistical analyses were performed using the Pkcross procedure, and Cohen's d was estimated for all response variables. There was no significant inter-period difference between the mean changes of body weight, waist circumference, and body mass index (BMI). Furthermore, no significant change was confirmed in participants' blood pressure, triglycerides, total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), very low-density lipoprotein (VLDL), serum homocysteine, high-sensitive c-reactive protein (hs-CRP), malondialdehyde (MDA), and total antioxidant capacity (TAC). It seems that the dose of FGE used in this study was not sufficient to cause any significant changes in the outcomes. Therefore, further studies with dose-response designs and longer durations are recommended.

A Machine Learning Approach to Assess Differential Item Functioning of the KINDL Quality of Life Questionnaire Across Children with and Without ADHD.

This study aimed to investigate differential item functioning (DIF) of the child and parent reports of the KINDL measure across children with and without Attention-deficit/hyperactivity disorder (ADHD). The sample included 122 children with ADHD and 1086 healthy peers, alongside 127 and 1061 of their parents, respectively. The generalized partial credit model with lasso penalization, as a machine learning method, was used to assess DIF of the KINDL across the two groups. The findings showed that three out of 24 items of the child reports and seven out of 24 items of the parent reports of the KINDL exhibited DIF between children with and without ADHD. Accordingly, Iranian children with and without ADHD along with their parents perceive almost all items in the KINDL similarly. Hence, the observed difference in quality of life scores between children with and without ADHD is a real difference and not a reflection of measurement bias.

Assessing whether child and parent reports of the KINDL questionnaire measure the same constructs of quality of life in children with attention-deficit hyperactivity disorder.

BACKGROUND: Discrepancy between child self-report and parent proxy-report has long been documented in the health-related quality of life (HRQoL) measurement of children with chronic health conditions. This study aims to assess whether child and parent reports of the Kinder Lebensqualität fragebogen (KINDL) questionnaire measure the same construct of HRQoL in children with attention-deficit hyperactivity disorders (ADHD). METHODS: Participants were 122 Iranian children with ADHD and 127 of their parents, who completed the child and parent reports of the KINDL, respectively. Internal consistency of the child and parent reports were assessed by Cronbach's alpha. The intra-class correlation (ICC) coefficient and factor analysis were applied to assess whether the child self-report and the parent proxy-report measured the same construct of HRQoL. Additionally, convergent and discriminant validity were assessed using the Spearman correlation. RESULTS: The results of factor analysis revealed that the child self-report and parent proxy-report measure two different aspects of HRQoL. Moreover, both versions of the KINDL instrument showed excellent convergent and discriminant validity. The internal consistency was close to or greater than 0.7 for all domains of both child and parent reports. CONCLUSIONS: Although the child self-report and the parent proxy-report of the Persian version of the KINDL have good psychometric properties, they are not interchangeable. This finding indicates that Iranian children with ADHD and their parents evaluate children's HRQoL from their own viewpoints.

Bacterial infections in the early period after liver transplantation in adults: A prospective single-center cohort study.

Liver transplantation (LT) is a potentially curative treatment for terminal stage hepatic diseases. Bacterial infections are the main causes of mortality and morbidity in the early period after LT. Identifying the risk factors could help in minimizing their development. We prospectively investigated the incidence, characteristics, and risk factors of bacterial infections among the recipients during hospitalization after LT and assigned a predictive score. All 389 consecutive adults who underwent LT at the main referral hospital of LT in Iran during 1 year were enrolled prospectively in a cohort study. Infection group consisted of 143 recipients (36.8%). Urinary tract and surgical site infections were the most frequent ones. Gram-negative bacteria were more prevalent than Gram-positive ones. Independent risk factors were female sex (relative risks = 2.13), age ≤ 43.5 years (3.70), hospital stay ≥ 9.5 days (5.22), abdominal reoperation (3.03), vancomycin-resistant Enterococci colonization (5.52), hospitalization 3 months prior to LT (3.25), mechanical ventilation ≥48 hr (4.93), and renal replacement therapies (13.40). We developed a risk score for the prediction of bacterial infections with an area under the receiver operating characteristic curve of 0.85 (95% CI, 0.81-0.89) with sensitivity of 88% and specificity of 64%. In the infection group, mortality was higher than in controls (18.9% vs. 2.0%) with longer hospitalization (16 vs. 10 days; P < 0.001). We detected a high rate of bacterial infections leading to longer hospital stay and higher mortality rate. The formulated risk score can help predict bacterial infections; however, it requires clinical validation in further studies.

Assessing the effect of child's gender on their father-mother perception of the PedsQL™ 4.0 questionnaire: an iterative hybrid ordinal logistic regression/item response theory approach with Monte Carlo simulation.

BACKGROUND: This study aimed at investigating the possible confounding effect of children's gender on the parents' dyads perception of their child HRQoL at both item and scale levels of PedsQLTM4.0 questionnaire. METHODS: The PedsQL™ 4.0 Generic Core Scales were completed by 573 children and their father-and-mother dyads. An iterative hybrid ordinal logistic regression/item response theory model with Monte Carlo simulation was used to detect differential item functioning (DIF) invariance across mothers/fathers and daughter/sons. RESULTS: Assessing DIF across mother-daughter, father-daughter, mother-son, and father-son dyads revealed that although parents and their children perceived the meaning of some items of PedsQLTM4.0 instrument differently, the pattern of fathers' and mothers' report does not vary much across daughters and sons. CONCLUSION: In the Persian version of PedsQLTM4.0, the child's gender is not a confounding factor in the mothers' and fathers' report with respect to their daughters' and sons' HRQoL. Hence, paternal proxy-reports can be included in studies, along with maternal proxy-reports, and the reports can be combined short of concerning children gender, when looking at parent-child agreement.

Evaluating prevalence of depression, anxiety and hopelessness in patients with Vitiligo on an Iranian population.

INTRODUCTION: Vitiligo is caused by partial or complete destruction of melanocytes in the affected skin area and influences the patient's quality of life. Besides physical involvement, vitiligo patients experience a high level of stress. Depression and Anxiety are common psychiatric disorders in vitiligo patients. AIM: This study, as the first study, evaluates hopelessness, anxiety, depression and general health of vitiligo patients in comparison with normal controls in an Iranian population. METHOD: Hundred patients with vitiligo and hundred healthy controls were examined. General health, depression, hopelessness and anxiety were evaluated based on general health questionnaire. Anxiety, depression and hopelessness levels were analyzed using Chi-Square, and the mean value of general health was evaluated through t-test. RESULTS: The results showed that anxiety and hopelessness levels were significantly higher in vitiligo patients than those who are in healthy controls. This significant difference refers to high levels of anxiety and hopelessness among women with vitiligo. It was also found that the single patients were more anxious, hopeless and depressive, while the married patients were only more anxious and hopeless than those who are in the control group, respectively. General health of patients was significantly worse than in healthy controls. The low level of general health in patients was related to poorer level of general health among women with vitiligo. CONCLUSION: It seems that women with vitiligo are more mentally stressed than men with vitiligo. Both singles and married vitiligo patients suffer from anxiety and hopelessness.

Assessing the measurement invariance of the RCADS-25 questionnaire across gender and child-parent dyads in the presence of multilevel data.

PURPOSE: This study aims to assess the measurement invariance of the short version of the Revised Child Anxiety and Depression Scale (RCADS-25) across male and female adolescents along with child self-reports and parent proxy-reports. METHODS: The sample consisted of 2039 adolescents and their parents from 51 public and private schools in Shiraz (southern Iran). The measurement invariance of the RCADS-25 was investigated by the multilevel multiple-indicators multiple-causes model. In addition, the reliability of the questionnaire was examined by Cronbach's alpha coefficient, and its validity was evaluated by exploratory and categorical confirmatory factor analysis. RESULTS: Although the RCADS-25 includes five (20%) non-invariant items across male and female adolescents, their impact is negligible at the scale level. In addition, 10 out of 25 items (40%) were non-invariant across self- and proxy-reports, which did not have substantial effect at the scale level. CONCLUSION: Based on our findings, the instrument can be used, albeit with caution, for comparing depression and anxiety scores between male and female adolescents as well as child self-reports and parent proxy-reports.

Assessing whether EORTC QLQ-30 and FACT-G measure the same constructs of quality of life in patients with total laryngectomy.

BACKGROUND: The European Organization for Research and Treatment of Cancer QOL Core Questionnaire 30 (EORTC QLQ-30) and the Assessment of Cancer Therapy-General (FACT-G) are the two most widely used measures of cancer-specific health-related quality of life (HRQOL). This study aims to assess whether the two instruments measure the same constructs of HRQOL in patients with total laryngectomy. METHODS: The EORTC QLQ-30 and the FACT-G was completed by 132 patients with total laryngectomy. Convergent, discriminant, and construct validity of the EORTC QLQ-C30 and the FACT-G were assessed by Spearman's correlation and explanatory factor analysis. RESULTS: The results of factor analysis showed that the EORTC QLQ-C30 and the FACT-G measure different aspects of HRQOL. Moreover, both instruments showed excellent convergent and discriminant validity, except for nausea and vomiting symptom subscale in the EORTC QLQ-C30 questionnaire. The internal consistency was close or greater than 0.7 for all domains of both instruments except for functional wellbeing in FACT-G. CONCLUSIONS: This study revealed that neither of the two instruments can be replaced by the other in the assessment of HRQOL in Iranian patients with total laryngectomy. Accordingly, clinicians should exactly define their research questions related to patient-reported outcomes before choosing which instrument to use.

Testing whether patients with diabetes and healthy people perceive the meaning of the items in the Persian version of the SF-36 questionnaire similarly: a differential item functioning analysis.

PURPOSE: It has been rarely studied whether observed disparity in health-related quality-of-life (HRQoL) scores between patients with diabetes and healthy individuals is due to differential item functioning (DIF) or a true difference in the underlying construct. This study aimed to examine DIF in the SF-36 questionnaire and its effect on comparing HRQoL scores between patients with diabetes and healthy people. METHODS: The sample consisted of 230 patients with type 2 diabetes and 642 healthy individuals who filled out the Persian version of the SF-36 questionnaire. To detect DIF across patients with diabetes and healthy individuals, multiple-group multiple-indicator multiple-causes model was used. In addition, item calibration strategy was used to determine whether the effect of item-level DIF was transferred to the scale level. RESULTS: Nine out of thirty-six (25 %) items were detected as DIF, of which one item (11 %) was flagged as uniform and eight items (89 %) as non-uniform DIF. Most of the DIF items were detected in the mental health component which includes vitality, perceived mental health and social functioning subscales rather than in physical health component. Moreover, nonsignificant latent mean differences for general health perception and social functioning subscales became significant after DIF calibration. CONCLUSION: The findings of the present study show that patients with diabetes and healthy individuals perceived some items in the SF-36 questionnaire differently. More importantly, in some subscales, the effect of item-level DIF was transferred to the scale level. Consequently, considerable caution should be taken in comparing HRQoL scores between patients with diabetes and healthy individuals.

Power and Sample Size Calculations in Clinical Trials with Patient-Reported Outcomes under Equal and Unequal Group Sizes Based on Graded Response Model: A Simulation Study.

OBJECTIVES: To provide a valid sample size strategy based on simulation and to evaluate the statistical power in clinical trials with patient-reported outcomes (PROs) based on a polytomous item response theory model-the graded response model (GRM)-and to compare this framework with the classical test theory (CTT) approach. METHODS: One thousand randomized clinical trials were simulated using PRO based on the GRM and under various combinations of the number of patients in each arm, the group allocation ratio, the number of items and categories, and group effects. The power and sample size estimated in the simulations were then compared with those computed using the CTT framework. RESULTS: The results indicated that the impact of the most influential factors, including the number of patients, group allocation ratio, group effects, and the number of categories, on the power and sample size of the GRM-based and CTT-based approaches was similar. Nevertheless, the strong impact of the number of items on these issues distinguished the two approaches. CONCLUSIONS: It is crucial to use an adapted sample size formula in a GRM-based analysis because the classical formula designed for the CTT-based approach does not consider the impact of the number of items, which could result in an inadequately sized study and a decrease in power. Thus, when clinicians design a randomized clinical trial with polytomous PRO endpoints using classical sample size formula as the base, they should be aware of the possibility of making an incorrect clinical decision.

Item-level informant discrepancies across obese-overweight children and their parents on the PedsQL™ 4.0 instrument: an iterative hybrid ordinal logistic regression.

PURPOSE: Child obesity has become a major health concern worldwide. In order to provide successful intervention strategies, it is necessary to understand how obese-overweight children and their parents perceive obesity and its consequences on child's health-related quality of life (HRQoL). This study aimed to assess measurement equivalence of the PedsQL™ 4.0 across obese-overweight children and their parents. METHODS: The items in the PedsQL™ 4.0 were analysed for differential item functioning (DIF) across obese-overweight children and their parents using an iterative hybrid ordinal logistic regression/item response theory approach. The sample included 647 overweight-obese children and their parents, who completed child and parent reports of the PedsQL™ 4.0, respectively. RESULTS: Overall, 17 out of 23 (74%) items were flagged with DIF across two groups: eight items exhibited uniform DIF and nine items non-uniform DIF. In addition, parents of obese children rated the child's HRQoL significantly lower than their children in all domains of the PedsQL™ 4.0, and this finding did not change whether or not items with uniform DIF were included. CONCLUSIONS: Although obese-overweight children and their parents interpret items of the PedsQL™ 4.0 in a conceptually different manner, removing or retaining DIF items in the subscales had no significant effects on group differences. Accordingly, it appears that observed differences in HRQoL scores across child and parent reports are a true difference and not a reflection of measurement artefact.

A randomized controlled trial of vitamin D supplementation on perinatal depression: in Iranian pregnant mothers.

BACKGROUND: Mood disorders in pregnancy and post-partum period are common and considered as a public health issue. Researchers have studied the relationship between low serum vitamin D concentration and perinatal depression, although no clinical trial has been conducted on vitamin D's effects on depression related to childbirth. This study evaluated the effect of vitamin D3 supplementation on perinatal depression scores. METHODS: This randomized clinical trial was done in pregnant women who were under prenatal care in a teaching hospital in Shiraz, Iran. The inclusion criteria were: being 18 years or older, no history of mental illness and internal diseases, a singleton live fetus, without any pregnancy complications, gestational age of 26-28 weeks upon enrollment, and depression score of 0 to 13. The Edinburgh Postnatal Depression scale was used to evaluate depression scores. A total of 169 participants were assigned to the two groups of placebo and vitamin D through block randomization design. Vitamin D group received 2000 IU vitamin D3 daily from 26 to 28 weeks of gestation until childbirth. Maternal serum 25-hydroxyvitamin D concentrations were measured at baseline and childbirth. Besides, depression scores were evaluated four times: at 26-28 and 38-40 weeks of gestation, and finally at 4 and 8 weeks after birth. RESULTS: The two groups were similar in relation to baseline 25-hydroxyvitamin D concentrations. However, at childbirth, the vitamin D group had significantly higher 25-hydroxyvitamin D concentration in comparison to the control group (p < 0.001). At baseline, no correlation was observed between 25-hydroxyvitamin D concentration and depression score (r = 0.13, p = 0.09). There was no significant difference between the two study groups in relation to the baseline depression score. While, the vitamin D group had greater reduction in depression scores than the control group at 38-40 weeks of gestation (p = 0.01) also, at 4 and 8 weeks after birth (p < 0.001). CONCLUSIONS: The present trial showed that consuming 2000 IU vitamin D3 daily during late pregnancy was effective in decreasing perinatal depression levels. We suggest further clinical trial in pregnant mothers who are at risk for postnatal depression. TRIAL REGISTRATION: Iranian Registry of Clinical Trials  IRCT2015020310327N11 . Date of registration: March 9th 2015.

Cross-cultural Measurement Equivalence of the KINDL Questionnaire for Quality of Life Assessment in Children and Adolescents.

This cross-cultural study aimed to assess whether Iranian and Serbian children, and also their parents, perceived the meaning of the items in the KINDL quality of life questionnaire consistently. The sample included 1086 Iranian and 756 Serbian children and adolescents, alongside 1061 and 618 of their parents, respectively. The ordinal logistic regression was used to assess differential item functioning (DIF) of the self and proxy-reports of the two versions of the KINDL, including Kid-KINDL and Kiddo-KINDL, across Iranian and Serbian samples. Statistically significant DIF was flagged for 14 out of 24 (58%) and 20 out of 24 (83%) items in the self-report of the Kid-KINDL and Kiddo-KINDL, respectively. Moreover, 20 out of 24 (83%) in the proxy reports of the both Kid-KINDL and Kiddo-KINDL, showed DIF across two samples. Accordingly, considerable caution is warranted when using the KINDL for cross-cultural comparisons.

Level of Agreement between Children with Asthma and their Parents on Quality of Life.

BACKGROUND: Child-parent agreement is a controversial aspect of measuring health-related quality of life (HRQoL) in children and adolescents. The aim of this study was to assess the agreement between the child self-reports and parent proxy reports of the PedsQL 3.0 Asthma Module in Iranian children with asthma to evaluate HRQoL. Moreover, the psychometric properties of the child and parent reports of the PedsQL 3.0 Asthma Module were assessed in the present study. METHODS: Participants were 112 children with asthma and their parents, who completed the Farsi version of the PedsQL 3.0 Asthma Module. The multitrait-multimethod correlation matrix and factor analysis were used to test whether the child self-reports and the parent proxy reports measured the same construct. Additionally, convergent and discriminant validity and internal consistency were assessed using the Pearson correlation. RESULTS: The correlation between the child and parent HRQoL perceptions ranged between 0.13 and 0.36 across the same domains. Our factor analysis revealed that the child self-reports and the parent proxy reports measured 2 different constructs of HRQoL. Furthermore, our findings showed that both the child self-reports and the parent proxy reports of the PedsQL 3.0 Asthma Module had excellent internal consistency and acceptable convergent and discriminant validity. CONCLUSION: Although the child self-reports and the parent proxy reports of the Farsi version of PedsQL 3.0 Asthma Module showed good psychometric properties, they were not interchangeable. Our children with asthma and their parents evaluated child HRQoL from their own viewpoints.

A cross-cultural study to assess measurement invariance of the KIDSCREEN-27 questionnaire across Serbian and Iranian children and adolescents.

PURPOSE: The KIDSCREEN questionnaire for health-related quality of life (HRQOL) assessments in children and adolescents was simultaneously developed across 13 European countries, and it was subsequently translated and culturally adapted to over 30 different languages across the world. The aim of this study was to evaluate the measurement equivalence of the KIDSCREEN-27 across Serbian and Iranian children and adolescents. METHODS: The items in the KIDSCREEN-27 were analyzed for differential item functioning (DIF) across Iranian and Serbian populations using ordinal logistic regression with three different criteria. The sample included 330 Iranian and 329 Serbian children and adolescents and 330 and 314 of their parents, respectively. RESULTS: Across the two samples, DIF was detected in 16 (59 %) of 27 items in the child self-reports and in 20 (74 %) of 27 items in the parent/proxy report. However, using alternative criteria based on magnitude detected for DIF, only three items in the parent/proxy report showed significant DIF. CONCLUSION: Our study provided more evidence that the KIDSCREEN-27 possesses DIF items across different cultures, but their impact is probably small, and the questionnaire could be used for cross-cultural HRQOL comparisons.

Testing parent dyad interchangeability in the parent proxy-report of PedsQL™ 4.0: a differential item functioning analysis.

PURPOSE: In child-parent agreement studies in the field of paediatric health-related quality of life (HRQoL), little attention has been paid to the effect of gender in parental proxy rating of children's HRQoL. This study aims to test the potential interchangeability of parent dyads in reporting children's HRQoL on both item and scale levels of the PedsQL™ 4.0 instrument, using the approach of differential item functioning (DIF). METHODS: The PedsQL™ 4.0 Generic Core Scales were completed by 576 father-and-mother dyads. A polytomous item response theory model, graded response model, was used to detect DIF across fathers and mothers. RESULT: Assessment at item level showed that fathers and mothers perceived the meaning of items of the PedsQL™ 4.0 consistently. Regarding the scale level, a moderate to high level of agreement was observed between mothers' and fathers' reports on all similar subscales. Although the significant mean score differences in total, physical and emotional functioning indicated that fathers gave higher scores to their children, the small effect size implied that this difference may not be practically meaningful. CONCLUSION: Our findings revealed that discrepancy in parent dyads in rating children's HRQoL is a "real" difference and not an artefact due to measurement non-invariance. Fathers were seen to have slightly different insights into their children, especially for emotional functioning, but overall the results were not all that different. This suggests that paternal proxy-reports can be included in studies along with maternal proxy-reports, and the two may be combined when looking at parent-child agreement. Parent-child agreement studies in Iran are not affected by parents' gender, and therefore, researchers may rely on the assumption of the interchangeability of fathers and mothers in these studies.

Validation of the Persian version of COOP/WONCA functional health status charts in liver transplant candidates.

CONTEXT: Health-related quality of life is a preferred outcome measure for patients with advanced liver disease. The functional health status charts developed by the Dartmouth Primary Care Cooperative Information Project (COOP)/World Organization of National Colleges, Academies and Academic Associations (WONCA) make up a generic instrument for assessing health-related quality of life. OBJECTIVE: To translate and validate the Persian version of COOP/WONCA in liver transplant candidates and to assess the correlation of Child Pugh classification and Model of End Stage Liver Disease (MELD) score with quality of life.Setting-The Shiraz liver transplant center, the most active liver transplant center in the Middle East. PARTICIPANTS: Consecutive adult outpatients waiting for their first liver transplant who attended follow-up visits in the pretransplant clinic.Main Outcome Measures-Patients completed COOP/WONCA along with the Short Form (SF)-36. Data on the underlying cause of cirrhosis, Child-Pugh classification, and MELD scores were collected from medical records. RESULTS: A Persian version of the COOP/WONCA was accepted by liver transplant candidates and showed adequate reliability and validity. Similar domains in COOP/WONCA charts and the SF-36 were highly correlated, indicating that construct validity of the COOP/WONCA in relation to the SF-36 was good (77% of correlations were as expected). Moreover, the exploratory factor analysis could not extract 2 different quality-of-life factors. These findings provide sufficient evidence to conclude that the Persian versions of COOP/WONCA charts and the SF-36 measure the same constructs of health-related quality of life and can be used interchangeably. Four of the 6 COOP/WONCA charts did not allow discrimination between groups of patients according to Child Pugh classification, indicating poor known group validity.

Measurement equivalence of the KINDL questionnaire across child self-reports and parent proxy-reports: a comparison between item response theory and ordinal logistic regression.

Measurement equivalence is a necessary assumption for meaningful comparison of pediatric quality of life rated by children and parents. In this study, differential item functioning (DIF) analysis is used to examine whether children and their parents respond consistently to the items in the KINDer Lebensqualitätsfragebogen (KINDL; in German, Children Quality of Life Questionnaire). Two DIF detection methods, graded response model (GRM) and ordinal logistic regression (OLR), were applied for comparability. The KINDL was completed by 1,086 school children and 1,061 of their parents. While the GRM revealed that 12 out of the 24 items were flagged with DIF, the OLR identified 14 out of the 24 items with DIF. Seven items with DIF and five items without DIF were common across the two methods, yielding a total agreement rate of 50 %. This study revealed that parent proxy-reports cannot be used as a substitute for a child's ratings in the KINDL.