METHODS: This 12-weeks randomized, double-blind and placebo-controlled study investigated the effects of a probiotic (Lactobacillus plantarum P8; 10 log CFU daily) on psychological, memory and cognition parameters in one hundred and three (P8 n = 52, placebo n = 51) stressed adults with mean age of 31.7 ± 11.1 years old. All subjects fulfilled the criteria of moderate stress upon diagnosis using the PSS-10 questionnaire.
RESULTS: At the end of study, subjects on P8 showed reduced scores of stress (mean difference 2.94; 95% CI 0.08 to 5.73; P = 0.048), anxiety (mean difference 2.82; 95% CI 0.35 to 5.30; P = 0.031) and total score (mean difference 8.04; 95% CI 0.73 to 15.30; P = 0.041) as compared to placebo after 4-weeks, as assessed by the DASS-42 questionnaire. Although plasma cortisol levels were only marginally different between placebo and P8 (mean difference 3.28 ug/dl; 95% CI -7.09 to 0.52; P = 0.090), pro-inflammatory cytokines such as IFN-γ (mean difference 8.07 pg/ml; 95% CI -11.2 to -4.93; P
Methods: The English-language validated questionnaires using data about demographics and monthly health records were translated into the Chinese language. Both forward and backward translated versions were validated.
Results: The developed demographic and monthly health questionnaires showed an overall item-level content validity index (I-CVI) of 0.99 and 0.97, respectively; while the translated Chinese versions showed I-CVI of 0.97 and 0.98, respectively. Item-level of response process validity index of 1.00 for this questionnaire was obtained from 30 respondents inferring that the items were clear and comprehensible.
Conclusions: This study showed acceptable levels validity in the Chinese translated version, illustrating a valid and reliable tool to be used for simultaneous assessment of gastrointestinal and respiratory tract-related illnesses in young children that is applicable for Malaysia's Chinese population and other Chinese-speaking nations.