Double-blindness protects scientific validity

Systematic Review and Meta-Analysis on the Effects of Astaxanthin on Human Skin Ageing

Context: Astaxanthin (ASX), a xanthophyll carotenoid derived from microalgae Haematococcus pluvialis, mitigating skin photoaging and age-related skin diseases by its antioxidant and anti-inflammatory effects in animal studies. Objective: The aim was to systematically evaluate if ASX applications have anti-ageing effects in humans. Methods: A comprehensive search of PubMed, Scopus and Web of Science found a total of eleven studies. Nine randomised, controlled human studies assessed oral ASX effects and two open-label, prospective studies evaluated topical, oral-topical ASX effects on skin ageing. GetData Graph Digitizer was used to extract mean values and standard deviations of baseline and endpoint, and Cochrane Collaboration’s tool assessed RoB for all included studies. Review Manager 5.4 was used to conduct meta-analysis of RCTs; the results were reported as effect size ± 95% confidence interval. Results: Oral ASX supplementation significantly restored moisture content (SMD = 0.53; 95% CI = 0.05, 1.01; I² = 52%; p = 0.03) and improved elasticity (SMD = 0.77; 95% CI = 0.19, 1.35; I² = 75%; p = 0.009) but did not significantly decrease wrinkle depth (SMD = −0.26; 95% CI = −0.58, 0.06; I² = 0%; p = 0.11) compared to placebo. Open-label, prospective studies suggested slightly protective effects of topical and oral-topical ASX applications on skin ageing. Conclusions: Ingestion and/or topical usages of ASX may be effective in reducing skin ageing and have promising cosmetical potential, as it improves moisture content and elasticity and reduces wrinkles.

Random Guess and Wishful Thinking are the Best Blinding Scenarios

Blinding is a methodologic safeguard of treatment evaluation, yet severely understudied empirically. Mathieu et al.'s theoretical analysis (2014) provided an important message that blinding cannot eliminate potential for bias associated with belief about allocation in randomized controlled trial; just like the intent-to-treat principle does not guarantee unbiased estimation under noncompliance, the blinded randomized trial as a golden standard may produce bias. They showed possible biases but did not assess how large the bias could be in different scenarios. In this paper, we examined their findings, and numerically assessed and compared the bias in treatment effect parameters by simulation under frequently encountered blinding scenarios, aiming to identify the most ideal blinding scenarios in practice. We conclude that Random Guess and Wishful Thinking (e.g., participants tend to believe they received treatment) are the most ideal blinding scenarios, incurring minimal bias. We also find some evidence that imperfect or partial blinding can be better than no blinding.

The efficacy and safety of once-daily quetiapine extended release in patients with schizophrenia switched from other antipsychotics: an open-label study in Chinese population

BACKGROUND

Non-adherence to antipsychotic medication in schizophrenic patients is common and associated with symptom relapse and poorer long-term outcomes. The risk factors for treatment non-adherence include dosing frequency and complexity. Besides, slower dose titration in an acute schizophrenic episode may lead to attenuated efficacy. Therefore, the convenient dosage regimen and rapid initiation scheme of quetiapine extended release (XR) were expected to provide better effectiveness and promote adherence in patients with schizophrenia. This study was implemented to assess the efficacy and safety of once-daily quetiapine XR in schizophrenic patients with switched from other antipsychotics which were suboptimal due to insufficient efficacy or tolerability.

METHODS

This was a 12-week, open-label study conducted in the Chinese population in Taiwan. Patients who had a score of 4 (moderate) or greater on any of the 7 items of the Positive and Negative Syndrome Scale (PANSS) Positive Symptom Subscale and needed to switch from previous antipsychotics were recruited. Quetiapine XR was administered at 300 mg on day 1, 600 mg on day 2 and up to 800 mg after day 2. From day 8 until the end of the study, the dose of quetiapine XR was adjusted within 400-800 mg per day, depending on the clinical response and tolerance of the patients. The variable of the primary outcome was the change from baseline to Week 12 in PANSS total and subscale scores. Secondary outcome was the baseline-to-endpoint difference in the Clinical Global Impression-Severity (CGI-S) scores of the participants.

RESULTS

Sixty-one patients were recruited and 55.7% of them completed the study. The mean changes in the PANSS total score and CGI-S score showed significant improvement (-18.4, p < .001 and -1.0, p < .001, respectively). Four patients (6.7%) experienced adverse events including headache, exacerbation of psychosis and dysuria. The use of concomitant anticholinergics decreased from 15.0% to 8.3%.

CONCLUSIONS

The results of our investigation implicated that quetiapine XR was an effective and well tolerated alternative for Chinese schizophrenic patients with previous suboptimal treatment. Future large-scale studies are warranted to validate our results.

TRIAL REGISTRATION

ClinicalTrials.gov ID NCT02142556 . Registered 15 May 2014.