Animal research plays an important role in the pre-clinical phase of clinical trials. In animal studies, the power analysis approach to sample size calculation is recommended. Whenever it is not possible to assume the standard deviation and the effect size, an alternative to the power analysis approach is the 'resource equation' approach, which sets the acceptable range of the error degrees of freedom (DF) in an analysis of variance (ANOVA). The aim of this article is to guide researchers in calculating the minimum and maximum numbers of animals required in animal research by reformulating the error DF formulas.

Planning a validation study of a questionnaire or measurement tool requires consideration for testing the validity and reliability aspects of the measurement tool. When it comes to the reliability aspect, a number of commonly used statistical coefficients such as Cronbach's alpha, intraclass correlation, kappa and Pearson's correlation coefficients would be considered to provide empirical evidence of the reliability of the tool during the validation process. To ensure that the reliability is accurately assessed, a researcher must consider the sample size requirement for the statistical analyses. In this article, I will introduce a newly developed web-based sample size calculator, which includes the ability to calculate the sample sizes of these four important coefficients. I will also show how to use the calculator for each of the coefficients.

Currently, there is no effective therapy for non-alcoholic fatty liver disease (NAFLD), although intensive calorie restriction is typically recommended but dietary adherence is an issue. The current study aimed to determine the effectiveness and adherence of eight weeks of modified alternate-day calorie restriction (MACR) in the control of NAFLD activity. This was a randomized controlled trial with MACR as the intervention and normal habitual diet as control. The outcome measures were body mass index (BMI), blood lipids, fasting blood sugar (FBS), liver enzymes (ALT and AST), and ultrasonographic measurements of liver steatosis and shear wave elastography (SWE). Per-protocol (PP) and intention-to-treat (ITT) analysis were performed within and between-groups with P < 0.05 as significant. 43 individuals with NAFLD satisfied study entry criteria, 33 were randomized to MACR and 10 to control group, and, 30 from MACR and 9 from control group completed PP. In between-group analysis of MACR vs. control, BMI were reduced in PP (P = 0.02) and ITT (P = 0.04). Only ALT was reduced in between-group analysis of MACR vs. control, both PP and ITT (P = 0.02 and 0.04 respectively). No reductions in all lipid parameters and FBS were found in between-group analyses (PP and ITT, all P > 0.22). Both liver steatosis grades and fibrosis (SWE) scores were reduced in between-group analyses of MACR vs. controls (PP and ITT, all P < 0.01). Adherence level remained between 75–83% throughout the study. As conclusion, 8 weeks of MACR protocol appears more effective than usual habitual diet in the control of NAFLD activity and with good adherence rate.

Respiratory tract infection (RTI) is a major public health challenge during the Muslim pilgrimage to Makkah. This study aims to evaluate the knowledge, attitude, and practice of Malaysian Hajj and Umrah pilgrims towards the prevention of RTIs in 2018 and determine correlations among three domains. A cross-sectional study was conducted among 225 Umrah and Hajj pilgrims. Knowledge, attitude, and practice (KAP) towards RTI prevention was assessed by using a validated self-administered questionnaire among pilgrims attending a weekly orientation course organized by private Hajj/Umrah companies. Out of 225 participants, 65.9% of respondents were female with the mean (SD) age of 46.74 (13.38) years. The interquartile range (IQR) score for knowledge is 18.0 (6.0), the mean scores of attitude and practice are 32.65 (4.72) and 25.30 (4.9). respectively. Significant and negative linear correlations between knowledge and practice (r = −0.232, p < 0.001), and attitude and practice (r = 0.134, p = 0.045) were observed. Results from the current study showed good knowledge of RTIs among Malaysian pilgrims. However, a poor attitude was reflected in their preventive practice behaviors. This will further help in the prevention and management of RTIs during Hajj and Umrah. Therefore, an extensive educational health campaign should be provided to pilgrims to create awareness.

Background: Hajj pilgrimage faces numerous challenges including a high prevalence of respiratory tract infection as well as its prevention strategies. The aim of this study was to develop and validate a questionnaire to evaluate knowledge, attitude and practice (KAP) towards respiratory tract infections (RTIs) prevention among Malaysian Hajj pilgrims. Methods: This study was conducted among Malaysian Umrah pilgrims in Malaysia from Kuala Lumpur and Kelantan. The questionnaire then underwent a series of validation process that included content, face validity and exploratory part. Item response theory (IRT) analysis was utilized for the validation of the knowledge domain. The attitude and practice were validated using the exploratory factor analysis (EFA). Results: The validation process resulted in a questionnaire that comprised of four main sections: demography, knowledge, attitude, and practice. Following IRT analysis of the knowledge domain, all items analyzed were within the acceptable range of difficulty and discrimination. The Kaiser-Meyer-Olkin measure of sampling adequacy (KMO) was 0.72 and 0.84 for attitude and practice domain respectively and Bartlett's test of Sphericity for both domains were highly significant (P < 0.001). The factor analysis resulted in two factors with total of 12 items in attitude domain, and 2 factors with total of 13 items in the practice domain with satisfactory factor loading (> 0.3). The Cronbach's alpha for reliability of the knowledge, attitude and practice domains all showed acceptable values of > 0.6 (0.92, 0.77 and 0.85). Conclusion: The findings of this validation and reliability study showed that the developed questionnaire had a satisfactory psychometric property for measuring KAP of Malaysian Hajj pilgrims.