Dimensions analysis of the Hospital Survey on Patient Safety Culture questionnaire in Iran: Psychometric properties.

AIM: The present study aimed to investigate the possible alternative factorial structure of the patient safety culture model in Iran. METHODS: This study was performed based on data collected by Hospital Survey on Patient Safety Culture (HSOPSC) questionnaire from 420 staff in four hospitals. Internal consistency reliability and construct validity were evaluated by Cronbach's alpha and correlation analysis. Exploratory factor analysis (EFA), confirmatory factor analysis (CFA) and structural equation modeling (SEM) were used to investigate the possible alternative factorial structure, examine and confirm the obtained structure, alternatively. Kaiser-Meyer-Olkin measure and Bartlett test were calculated to determine the factor ability of sample and fit of the factor analysis, alternatively. SPSS and AMOS version 25 were used. RESULTS: EFA identified 12 dimensions which one dimension has been also created from a new question. Distribution of items in all dimensions differed from the original HSOPSC questionnaire except two dimensions. The obtained structure was a proportional model. The calculation of Cronbach's alpha (∝ = .8) showed that, the internal consistency reliability was appropriate for all items in the questionnaire. Also, construct validity was acceptable for all factors. CONCLUSIONS: The structure of the dimensions obtained in this study was not consistent with the structure of the original HSOPSC model. HIGHLIGHTS: Provide a model for assessing patient safety culture with relative stability with respect to the native culture of the region. Good content and construct validity. Differences in the distribution of items in dimensions. Formation of new dimensions. Performing a psychometric analysis of the instrument using EFA, CFA and SEM to examine the disagreement on the validity, reliability and dimensions of patient safety culture in previous studies in Iran. Numerous discrepancies in item wording comply with the approach advocated by the translation guideline for AHRQ survey on patient safety.

Prognostic Factors for Survival in Patients with Gastric Cancer using a Random Survival Forest

Background: Gastric cancer is the fifth most common cancer and the third top cause of cancer related death with about 1 million new cases and 700,000 deaths in 2012. The aim of this investigation was to identify important factors for outcome using a random survival forest (RSF) approach. Materials and Methods: Data were collected from 128 gastric cancer patients through a historical cohort study in Hamedan-Iran from 2007 to 2013. The event under consideration was death due to gastric cancer. The random survival forest model in R software was applied to determine the key factors affecting survival. Four split criteria were used to determine importance of the variables in the model including log-rank, conversation?? of events, log-rank score, and randomization. Efficiency of the model was confirmed in terms of Harrell's concordance index. Results: The mean age of diagnosis was 63 ±12.57 and mean and median survival times were 15.2 (95%CI: 13.3, 17.0) and 12.3 (95%CI: 11.0, 13.4) months, respectively. The one-year, two-year, and three-year rates for survival were 51%, 13%, and 5%, respectively. Each RSF approach showed a slightly different ranking order. Very important covariates in nearly all the 4 RSF approaches were metastatic status, age at diagnosis and tumor size. The performance of each RSF approach was in the range of 0.29-0.32 and the best error rate was obtained by the log-rank splitting rule; second, third, and fourth ranks were log-rank score, conservation of events, and the random splitting rule, respectively. Conclusion: Low survival rate of gastric cancer patients is an indication of absence of a screening program for early diagnosis of the disease. Timely diagnosis in early phases increases survival and decreases mortality.