Journal of Epidemiology
Online ISSN : 1349-9092
Print ISSN : 0917-5040
ISSN-L : 0917-5040
Volume 26, Issue 8
Displaying 1-7 of 7 articles from this issue
Review Article
  • Darko Nedovic, Nikola Panic, Roberta Pastorino, Walter Ricciardi, Stef ...
    2016 Volume 26 Issue 8 Pages 399-404
    Published: August 05, 2016
    Released on J-STAGE: August 05, 2016
    Advance online publication: June 25, 2016
    The STrengthening the REporting of Genetic Association studies (STREGA) statement was based on the STrengthening the REporting of OBservational studies in Epidemiology (STROBE) statement, and it was published in 2009 in order to improve the reporting of genetic association (GA) studies. Our aim was to evaluate the impact of STREGA endorsement on the quality of reporting of GA studies published in journals in the field of genetics and heredity (GH). Quality of reporting was evaluated by assessing the adherence of papers to the STREGA checklist. After identifying the GH journals that endorsed STREGA in their instructions for authors, we randomly appraised papers published in 2013 from journals endorsing STREGA that published GA studies (Group A); in GH journals that never endorsed STREGA (Group B); in GH journals endorsing STREGA, but in the year preceding its endorsement (Group C); and in the same time period as Group C from GH journals that never endorsed STREGA (Group D). The STREGA statement was referenced in 29 (18.1%) of 160 GH journals, of which 18 (62.1%) journals published GA studies. Among the 18 journals endorsing STREGA, we found a significant increase in the overall adherence to the STREGA checklist over time (A vs C; P < 0.0001). Adherence to the STREGA checklist was significantly higher in journals endorsing STREGA compared to those that did not endorse the statement (A vs B; P = 0.04). No significant improvement was detected in the adherence to STREGA items in journals not endorsing STREGA over time (B vs D; P > 0.05). The endorsement of STREGA resulted in an increase in quality of reporting of GA studies over time, while no similar improvement was reported for journals that never endorsed STREGA.
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Original Article
  • Tomoaki Matsuo, Hiroyuki Sasai, Rina So, Kazunori Ohkawara
    2016 Volume 26 Issue 8 Pages 405-412
    Published: August 05, 2016
    Released on J-STAGE: August 05, 2016
    Advance online publication: February 06, 2016
    Supplementary material
    Background: Does asking for the percentage of time spent sitting during work (P-method) instead of asking for the absolute length of time spent sitting (T-method) improve properties of the workers’ sitting- and walking-time questionnaire (WSWQ)? The purpose of this study was to investigate whether questioning technique influences test-retest reliability and criterion validity of the WSWQ.
    Methods: Sixty-five Japanese workers completed each version of the WSWQ in random order. Both questionnaires assessed quantities of time spent sitting or walking (including standing) during work time, non-working time on a workday, and anytime on a non-workday. Participants wore the thigh-worn inclinometer (activPAL) as criterion measure. Intraclass correlation coefficients (ICC) and Spearman’s ρ were used for the analyses.
    Results: For all three domains, values of reliability and validity with the P-method tended to be higher than with the T-method: ICC values ranged from 0.48–0.85 for the T-method and from 0.71–0.85 for the P-method; Spearman’s ρ values ranged from 0.25–0.58 for the T-method and from 0.42–0.65 for the P-method. The validities with both methods on a workday (0.51–0.58 for the T-method and 0.56–0.65 for the P-method) were higher than validities on a non-workday (0.25–0.45 for the T-method and 0.42–0.60 for the P-method). In post-survey interviews, 48 participants (77%) chose the P-method as their preferred questioning style.
    Conclusions: The study revealed that the P-method WSWQ had better reliability, validity, and ease of answering than the T-method, suggesting that the P-method can improve properties of the WSWQ and consequently advance the quality of epidemiological surveys in this field.
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  • Chia-Hsiang Hsu, Yiing-Jenq Chou, Christy Pu
    2016 Volume 26 Issue 8 Pages 413-419
    Published: August 05, 2016
    Released on J-STAGE: August 05, 2016
    Advance online publication: February 20, 2016
    Background: Although many studies have reported that high-quality continuity of care (COC) is associated with improved patient outcomes for patients with diabetes, few studies have investigated whether this positive effect of COC depends on the level of diabetes severity.
    Methods: A total of 3781 newly diagnosed diabetic patients selected from the 2005 National Health Insurance database were evaluated for the period 2005–2011. Generalized estimating equations combined with negative binomial estimation were used to determine the influence of COC on the overall emergency room (ER) use and diabetes mellitus (DM)-specific ER use. Analyses were stratified according to diabetes severity (measured using the Diabetes Complications Severity Index [DCSI]), comorbidities (measured using the Charlson comorbidity score), and age.
    Results: COC effects varied according to diabetes severity. Stratified analysis showed that the positive effect of COC on DM-specific ER use was the highest for a DCSI of 0 (least severe), with an incidence rate ratio (IRR) of 0.49 (95% CI, 0.41–0.59) in the high-COC group (reference group: low-COC group). Compared with the low-COC group, high-quality COC had a significant beneficial effect on overall ER use in younger patients (IRR 0.51; 95% CI, 0.39–0.66 for the youngest [18–40 years] group, and IRR 0.67; 95% CI, 0.59–0.76 for the oldest [>65 years] group) and those with a high number of comorbidities.
    Conclusions: The positive effects of high-quality COC on the treatment outcomes of patient with diabetes, based on the overall and DM-specific ER use, depends on the level of disease severity. Therefore, providing health education to enhance high-quality COC when the disease severity is low may be critical for ensuring optimal positive effects during diabetes disease progression.
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  • Yuta Yokoyama, Ribeka Takachi, Junko Ishihara, Yuri Ishii, Shizuka Sas ...
    2016 Volume 26 Issue 8 Pages 420-432
    Published: August 05, 2016
    Released on J-STAGE: August 05, 2016
    Advance online publication: April 09, 2016
    Supplementary material
    Background: Longitudinal epidemiological studies require both the periodic update of intake information via repeated dietary survey and the minimization of subject burden in responding to questionnaires. We developed a 66-item Food Frequency Questionnaire (short-FFQ) for the Japan Public Health Center-based prospective Study for the Next Generation (JPHC-NEXT) follow-up survey using major foods from the FFQ developed for the original JPHC Study. For the JPHC-NEXT baseline survey, we used a larger 172-item FFQ (long-FFQ), which was also derived from the JPHC-FFQ. We compared the validity of ranking individuals by levels of dietary consumption by these FFQs among residents of selected JPHC-NEXT study areas.
    Methods: From 2012 to 2013, 240 men and women aged 40–74 years from five areas in the JPHC-NEXT protocol were asked to respond to the long-FFQ and provide 12-day weighed food records (WFR) as reference; 228 also completed the short-FFQ. Spearman’s correlation coefficients (CCs) between estimates from the FFQs and WFR were calculated and corrected for intra-individual variation of the WFR.
    Results: Median CC values for energy and 53 nutrients for the short-FFQ for men and women were 0.46 and 0.44, respectively. Respective values for the long-FFQ were 0.50 and 0.43. Compared with the long-FFQ, cross-classification into exact plus adjacent quintiles with the short-FFQ ranged from 68% to 91% in men and 58% to 85% in women.
    Conclusions: Similar to the long-FFQ, the short-FFQ provided reasonably valid measures for ranking middle-aged and elderly Japanese for many nutrients and food groups. The short-FFQ can be used in follow-up surveys in prospective cohort studies aimed at updating diet rank information.
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  • Ang Zhao, Renjie Chen, Yongqing Qi, Ailan Chen, Xinyu Chen, Zijing Lia ...
    2016 Volume 26 Issue 8 Pages 433-439
    Published: August 05, 2016
    Released on J-STAGE: August 05, 2016
    Advance online publication: March 05, 2016
    Background: Road-traffic injury (RTI) is a major public-health concern worldwide. However, the effectiveness of laws criminalizing drunk driving on the improvement of road safety in China is not known.
    Methods: We collected daily aggregate data on RTIs from the Guangzhou First-Aid Service Command Center from 2009 to 2012. We performed an interrupted time-series analysis to evaluate the change in daily RTIs before (January 1, 2009, to April 30, 2011) and after (May 1, 2011, to December 31, 2012) the criminalization of drunk driving. We evaluated the impact of the intervention on RTIs using the overdispersed generalized additive model after adjusting for temporal trends, seasonality, day of the week, and holidays. Daytime/Nighttime RTIs, alcoholism, and non-traffic injuries were analyzed as comparison groups using the same model.
    Results: From January 1, 2009, to December 31, 2012, we identified a total of 54 887 RTIs. The standardized daily number of RTIs was almost stable in the pre-intervention period but decreased gradually in the post-intervention period. After the intervention, the standardized daily RTIs decreased 9.6% (95% confidence interval [CI], 6.5%–12.8%). There were similar decreases for the daily daytime and nighttime RTIs. In contrast, the standardized daily cases of alcoholism increased 38.8% (95% CI, 35.1%–42.4%), and daily non-traffic injuries increased 3.6% (95% CI, 1.4%–5.8%).
    Conclusions: This time-series study provides scientific evidence suggesting that the criminalization of drunk driving from May 1, 2011, may have led to moderate reductions in RTIs in Guangzhou, China.
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  • Masaru Sakurai, Junji Kobayashi, Yasuo Takeda, Shin-Ya Nagasawa, Junic ...
    2016 Volume 26 Issue 8 Pages 440-446
    Published: August 05, 2016
    Released on J-STAGE: August 05, 2016
    Advance online publication: April 16, 2016
    Supplementary material
    Aims: The present study aimed to investigate relationships among abdominal obesity, metabolic abnormalities, and the prevalence of chronic kidney disease (CKD) in relatively lean Japanese men and women.
    Participants and methods: The participants included 8133 men and 15 934 women between 40 and 75 years of age recruited from the government health check-up center in Kanazawa City, Japan. The prevalence of abdominal obesity, high blood pressure, dyslipidemia, and high fasting plasma glucose levels were assessed according to the Japanese criteria for metabolic syndrome. The estimated glomerular filtration rate (eGFR) was calculated using the modified Modification of Diet in Renal Disease equation for the Japanese population, and participants with an eGFR <60 mL/min/1.73 m2 and/or proteinuria were diagnosed with CKD.
    Results: Overall, 23% of males and 14% of females met criteria for CKD. Having more numerous complicated metabolic abnormalities was significantly associated with a higher odds ratio (OR) of CKD for men and women, irrespective of abdominal obesity. However, there was a sex difference in the OR of CKD for obese participants without metabolic abnormalities, such that abdominal obesity without metabolic abnormalities was significantly associated with a higher OR for men (multivariate-adjusted OR 1.63; 95% confidence interval [CI], 1.16–2.28) but not for women (OR 1.01; 95% CI, 0.71–1.44).
    Conclusions: The present findings demonstrated that obesity without metabolic abnormalities was associated with a higher risk of CKD in men but not women in a relatively lean Japanese population.
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