1.Subgroup Analysis in Meta-Analysis: a comparison of different methods
Yushi NAKANISHI ; Shigeyuki TOYOIZUMI ; Akihiro NAKAJIMA ; Chikuma HAMADA
Japanese Journal of Pharmacoepidemiology 2007;12(2):13-24
Introduction : Meta-analysis is well recognized as the most important study methodology in pharmacoepidemiology. The cause of heterogeneity of the effects among studies in the conventional meta-analyses, has been typically analyzed by meta-regression and sometimes by extracting several studies in a post hoc manner, constructing subgroups from these studies and analyzing the effect in this subgroup. However, if multiple study subgroups are produced in a post hoc manner, since the potential possible number of subgroups is very huge, the multiplicity of testing results in the inflation of the type I error rate. Therefore, even when a significant subgroup has been identified, it can represent a type I error, due to multiplicity of testing. To insist on the significance of a post hoc subgroup analysis, it is indispensable to conduct an analysis adjusted for multiplicity.
Objective : The present study was undertaken to establish a method for resolving the problem for the multiplicity of subgroup analysis in meta-analysis.
Methods : Performance comparisons among the Bonferroni method, the Holm method, the Scheffe type method and the closed testing procedure were conducted, assuming the actual meta-analysis of clinical studies on colon cancer.
Results : In the subgroup analysis without adjustment for multiplicity, the probability of type I error was unacceptably high. On the other hand, the four methods mentioned above can control this probability to below the nominal significance level. Under many situations, the closed testing procedure showed a relatively higher power, and this method was particularly superior to the other methods when a relatively high percentage of studies revealed minor effects.
2.A comparison of physical characteristics in starters and non-starters in a Japanese university rugby football players
Akihiro HIRATA ; Tetsuya NAKAJIMA ; Sayumi IWAMOTO ; Yuko OGUMA ; Naohiko KOTAKE
Japanese Journal of Physical Fitness and Sports Medicine 2022;71(6):523-530
The purpose of this study was to compare the characteristics of starters and non-starters with respect to the anthropometric and physical fitness in a Japanese university rugby team. Our sample pool consisted of 54 players of the K University rugby team, who were registered for the official games (all 7 games/year) in 2018 and 2019. The starter group (26 players) comprised of players with more than 3 games/year while the non-starter group (28 players) comprised of players that registered for official games but played less than 3 games. Anthropometric parameters, such as height, body mass, skinfold (8 items), girth (5 items), body composition, muscular strength, intermittent endurance, and sprint time, were assessed. We found that the starter group for forwards had lower skinfold (Biceps, Iliac crest, Supraspinale, Abdominal, Front thigh, and Medial calf) and percentage body fat than in the non-starter group. The starter group for backs had muscle strength of narrow chinning is higher than in the non-starter group. Finally, our study helped to clarify the physical factors that influence the difference in athletic performance between starters and non-starters in university rugby team. The forward starters had lower percentage body fat and better body composition and backs starters had better narrow chinning. The findings provide information to university rugby players who want to become starters, as well as help the coaching staff understand the factors that need to be strengthened in the players.
3.Prognosis of biopsy-confirmed metabolic dysfunction- associated steatotic liver disease: A sub-analysis of the CLIONE study
Michihiro IWAKI ; Hideki FUJII ; Hideki HAYASHI ; Hidenori TOYODA ; Satoshi OEDA ; Hideyuki HYOGO ; Miwa KAWANAKA ; Asahiro MORISHITA ; Kensuke MUNEKAGE ; Kazuhito KAWATA ; Tsubasa TSUTSUMI ; Koji SAWADA ; Tatsuji MAESHIRO ; Hiroshi TOBITA ; Yuichi YOSHIDA ; Masafumi NAITO ; Asuka ARAKI ; Shingo ARAKAKI ; Takumi KAWAGUCHI ; Hidenao NORITAKE ; Masafumi ONO ; Tsutomu MASAKI ; Satoshi YASUDA ; Eiichi TOMITA ; Masato YONEDA ; Akihiro TOKUSHIGE ; Yoshihiro KAMADA ; Hirokazu TAKAHASHI ; Shinichiro UEDA ; Shinichi AISHIMA ; Yoshio SUMIDA ; Atsushi NAKAJIMA ; Takeshi OKANOUE ;
Clinical and Molecular Hepatology 2024;30(2):225-234
Background/Aims:
Metabolic dysfunction-associated steatotic liver disease (MASLD) was recently proposed as an alternative disease concept to nonalcoholic fatty liver disease (NAFLD). We aimed to investigate the prognosis of patients with biopsy-confirmed MASLD using data from a multicenter study.
Methods:
This was a sub-analysis of the Clinical Outcome Nonalcoholic Fatty Liver Disease (CLIONE) study that included 1,398 patients with NAFLD. Liver biopsy specimens were pathologically diagnosed and histologically scored using the NASH Clinical Research Network system, the FLIP algorithm, and the SAF score. Patients who met at least one cardiometabolic criterion were diagnosed with MASLD.
Results:
Approximately 99% of cases (n=1,381) were classified as MASLD. Patients with no cardiometabolic risk (n=17) had a significantly lower BMI than patients with MASLD (20.9 kg/m2 vs. 28.0 kg/m2, P<0.001), in addition to significantly lower levels of inflammation, ballooning, NAFLD activity score, and fibrosis stage based on liver histology. These 17 patients had a median follow-up of 5.9 years, equivalent to 115 person-years, with no deaths, liver-related events, cardiovascular events, or extrahepatic cancers. The results showed that the prognosis for pure MASLD was similar to that for the original CLIONE cohort, with 47 deaths and one patient who underwent orthotopic liver transplantation. The leading cause of death was extrahepatic cancer (n=10), while the leading causes of liver-related death were liver failure (n=9), hepatocellular carcinoma (n=8), and cholangiocarcinoma (n=4).
Conclusions
Approximately 99% of NAFLD cases were considered MASLD based on the 2023 liver disease nomenclature. The NAFLD-only group, which is not encompassed by MASLD, had a relatively mild histopathologic severity and a favorable prognosis. Consequently, the prognosis of MASLD is similar to that previously reported for NAFLD.
4.Effect of COVID-19-restrictive measures on ambient particulate matter pollution in Yangon, Myanmar.
Win-Yu AUNG ; PAW-MIN-THEIN-OO ; Zaw-Lin THEIN ; Sadao MATSUZAWA ; Takehiro SUZUKI ; Yo ISHIGAKI ; Akihiro FUSHIMI ; Ohn MAR ; Daisuke NAKAJIMA ; Tin-Tin WIN-SHWE
Environmental Health and Preventive Medicine 2021;26(1):92-92
BACKGROUND:
Particulate matter (PM) is recognized as the most harmful air pollutant to the human health. The Yangon city indeed suffers much from PM-related air pollution. Recent research has interestingly been focused on the novel subject of changes in the air quality associated with the restrictive measures in place during the current coronavirus disease-2019 (COVID-19) pandemic. The first case of COVID-19 in Myanmar was diagnosed on March 23, 2020. In this article, we report on our attempt to evaluate any effects of the COVID-19-restrictive measures on the ambient PM pollution in Yangon.
METHODS:
We measured the PM concentrations every second for 1 week on four occasions at three study sites with different characteristics; the first occasion was before the start of the COVID-19 pandemic and the remaining three occasions were while the COVID-19-restrictive measures were in place, including Stay-At-Home and Work-From-Home orders. The Pocket PM
RESULTS:
The results showed that there was a significant reduction (P < 0.001) in both the PM
CONCLUSIONS
We concluded that the restrictive measures which were in effect to combat the COVID-19 pandemic had a positive impact on the ambient PM concentrations. The changes in the PM concentrations are considered to be largely attributable to reduction in anthropogenic emissions as a result of the restrictive measures, although seasonal influences could also have contributed in part. Thus, frequent, once- or twice-weekly Stay-At-Home or Telework campaigns, may be feasible measures to reduce PM-related air pollution. When devising such an action plan, it would be essential to raise the awareness of public about the health risks associated with air pollution and create a social environment in which Telework can be carried out, in order to ensure active compliance by the citizens.
Air Pollution/analysis*
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COVID-19/epidemiology*
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Humans
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Myanmar/epidemiology*
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Pandemics
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Particulate Matter/analysis*
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SARS-CoV-2