Korean Journal Of Family Medicine Research Articles

Articles Published in Korean Journal of Family Medicine: Impact of COVID-19 on Study Trends.

The Korean Journal of Family Medicine (KJFM), which is an official journal of the Korean Academy of Family Medicine, is an English-text medical journal published since 2009. Although nearly 15 years have passed since the journal was launched, to the best of our knowledge, no study has reviewed articles published in the KJFM. Accordingly, we analyzed articles published in the KJFM for the first time. Articles published in the KJFM between January 2018 and November 2023 were categorized according to article type. Information about author affiliations, study subjects, research methods, and modes of data collection was then scrutinized. Moreover, we compared the frequencies of subjects, research methods and modes of data collection before, during, and after the coronavirus disease 2019 pandemic. Original article was the most common article type. Approximately 52% of the articles were published by authors affiliated with departments other than family medicine, and 40% were published by family medicine. Approximately 60% and 38% of the articles were published by Korean authors and authors of international affiliations, respectively. Throughout the pandemic periods, research subjects focusing on "diseases & symptoms" have diminished, while "principles of family medicine" have progressively increased. Additionally, the use of cross-sectional study methods has declined. In terms of data collection, the use of "big data," "medical records," and "questionnaires" has decreased, whereas the use of "study results" has increased. KJFM is journal with wide and international participation covering various research subjects and study methods. We believe that our study provides valuable data for the future direction and development of the KJFM.

Review Article of the Korean Journal of Family Medicine

Review Article of the Korean Journal of Family Medicine

False Replies on Smoking Rate Surveys and an In-Hospital Smoking Cessation Clinic.

Cigarette smoking is a leading risk factor for cancer and cardiovascular and pulmonary disorders. It has been recommended that primary care physicians inquire about a patient's smoking status and recommend smoking cessation during every medical consultation.1) Thus, smoking rates and smoking cessation have been major topics in papers published in the Korean Journal of Family Medicine. In this issue, Kim et al.2) report a discrepancy between self-reporting and urine cotinine-verified smoking status in South Korea. Among 3,477 men, urine cotinine-verified smoking rates were 11.1% higher than the self-reported smoking rate. About 1 in 3 participants did not complete a smoking questionnaire or gave false replies. Age greater than 60 years, an educational level of high school graduation or lower, multiple health check-ups, and urine cotinine levels <500 ng/mL were associated with a discrepancy between the smoking rates in the self-reported and cotinine-verified groups. This study was performed in a single hospital unit. However, the results were similar to those of previous studies, which showed that, compared to smoking rates determined by counter-verification with biomarkers, smoking rates in self-reports are lower in populations that are pressured to abstain from cigarette smoking for medical or social reasons, such as pregnant women,3,4) teenagers,5) those undergoing treatment for smoking cessation,6) and those with pulmonary disorders.7) Another study by Shin et al.8) presented the results of compliance and effectiveness of a smoking cessation program started in hospitalized patients. Of these, 74.5% were cardiovascular disease patients who were referred from neurology and cardiology and who needed to stop smoking for secondary prevention. However, only 67.9% of the referred patients actually had a consultation and prescription. Moreover, even those patients who were prescribed a medicine to quit smoking through a consultation rarely revisited the outpatient clinic after discharge from the hospital. This study indicated that there were various obstacles to treatment in terms of referring hospitalized patients to the smoking cessation clinic. The authors state that it is imperative to introduce a systematic smoking cessation program, which emphasizes the relationship between smoking and disease, for hospitalized patients and to encourage cooperation to improve the smoking cessation rate. After the implementation of a new tax policy that raised the cigarette price in South Korea, smoking cessation treatment gained support from the National Health Insurance Program. Under these circumstances, primary care physicians are likely to encounter more patients with tobacco addiction problems. Therefore, they should be familiar with smoking cessation counseling and treatment regimens.

Jumping up to the Next Step toward the World's Leading Journal in Primary Care Medicine.

Dear Readers of the Korean Journal of Family Medicine (KJFM), I am the new editor-in-chief of the KJFM, Seung-Kwon Myung, M.D., Ph.D. at the Department of Family Medicine, National Cancer Center, Korea. It's my great honor and pleasure to become the editor-in-chief of this journal newly, but on the other hand, I feel a great deal of burden and responsibility to develop the quality of the KJFM. In this editorial, I would like to briefly tell our readers my key plans to make the KJFM jump up to the next step toward the world' leading journal in primary care medicine. First, the KJFM will try to publish more papers than the past and more frequently. Definitely, one of the important aims of the journal might be to make many readers read and cite its papers as frequently as possible. Being an 'online-only' publication allows the journal to publish more papers than a print journal and save the cost of publishing. As of January 2014, the KJFM turned to online only publication. Also, in order to publish more papers, we will improve the current peer-review process including shortening the review period and consider employing PLOS ONE's 'publish first, judge later' publication concept.1) This idea does not use the perceived importance of a paper as a criterion for acceptance or rejection. Instead, they publish any paper that is methodologically sound or any research that was conducted rigorously, and leave it to the scientific community to ascertain importance, post publication, through debated and comment.2) Due to PLOS ONE's unique publication methodology and business strategy, since its publication of 138 articles in the first year, 2006, PLOS ONE published 31,500 papers in 2013, and its 2013 impact factor was 3.534.3) Although there are some critiques on PLOS ONE's publication strategy, its strengths could be adopted for the development of our journal. Second, we will invite outstanding foreign university professors of the department of family medicine or other researchers in the field of primary care medicine as international editors in the KJFM. This helps our journal to be known to many primary care physicians around the world. More importantly, one of the criteria for being selected in the Science Citation Index (SCI) is the international diversity of the editorial board members. Last, we will make every effort to let the KJFM be indexed in the SCI in the near future. The Thomson Reuters journal selection process mainly considers the journal's basic publishing standards (e.g., timeliness of publication, international editorial conventions, full text English, and peer review), its editorial content, the international diversity of its authorship, and the citation data associated with it.4) To meet these criteria, we will thoroughly review the KJFM publishing process and ameliorate it. I hope the KJFM readers and members of the Korean Academy of Family Medicine take an active interest in our journal's development and give advice.

Comparison of research trends in korean and international family medicine in journals of family medicine.

BackgroundResearch is important for the development of family medicine as a professional field in primary care. The aim of this study was to suggest directions for the development of family medicine research by analyzing research trends in original papers published in the Korean Journal of Family Medicine (KJFM) and international journals.MethodsWe investigated original research papers published in KJFM and 4 international journals from August 2009 to July 2010. Analysis was conducted according to research topics, authors, methods, participants, and data sources.Results'Clinical research' was the most common research topic in both the KJFM (88.3%) and international journals (57.3%); however, international journals had more studies in other domains ('education and research,' 'health service,' and 'family medicine'). More authors other than family physicians participated in international journals than in the KJFM (58% and 3.3%, respectively). Most studies were 'cross-sectional' in KJFM (77.0%) and international journals (51.5%): however, the latter had more 'qualitative' studies, 'cohort' studies, and 'systematic reviews' than the former. The largest study population was 'visitors of health promotion center' in the KJFM and 'outpatients' in international journals. Most of the study sources were 'survey' and 'medical records' in both.ConclusionThere were limitations of diversity in the papers of the KJFM. Future investigation on papers of other than family medicine journals should be planned to assess research trends of family physicians.

Case reports in the korean journal of family medicine.

Besides original articles, other types of manuscripts in the Korean Journal of Family Medicine (KJFM) include review articles, brief communications, editorials, letters to the editor-in-chief, and case reports. Recently our editors discussed the case report guidelines of the KJFM. A case report by other specialists was submitted. Many family physicians were unfamiliar with this case, however, it was well known within its specialty area and was previously reported several times in other medical journals. They argued that the case would be instructive in differentiating other common diseases from the symptoms described. After some debate we made the decision to reject this case primarily because the patient directly visited specialists in a tertiary hospital, and was treated without the involvement of any family doctors or primary care physicians. The information for authors of KJFM describes about prerequisites for case reports as this.1) 'A case example should be one that has never been observed up to the present time and has never been reported before. If the case example is determined to be significant enough, although it may relate to a very common condition or a description that may not be appropriate to delineate, decision to accept the article shall be determined following the review of the editorial committee.' Considering that most of our readers are working in the primary care field, there are many interesting cases from other specialties which are similar to this case. Even if it is related with common symptoms, we thought primary care physicians should contact the patients first during the course. In addition, brief communication is another example that needs more detailed guidelines.

Need for Clinical Trial Registry and Institutional Review Board Approval in Human Subjects Research

In 2013, two important changes will occur in the Korean Journal of Family Medicine (KJFM) policy. One is mandatory registration of clinical trials before submission to KJFM, and the other is to required institutional review board (IRB) approval of all research involving subjects. A clinical trials registry is an official platform for registering a clinical trial. ClinicalTrials.gov, run by the US National Library of Medicine, was the first online registry for clinical trials and is the largest and most widely used today. The goal of a clinical trials registry is to provide increased transparency and access to clinical trials to the public.1) Clinical trials registries may decrease selective outcome reporting and further selective reporting bias.2) The International Committee of Medical Journal Editors decided that from July 1, 2005 no trials will be considered for publication unless they are included on a clinical trials registry.3) The World Health Organization has begun the push for clinical trial registration with the initiation of the International Clinical Trials Registry Platform. The Clinical Research Information Service is South Korea's registry, and is available http://cris.nih.go.kr/cris/index.jsp. It is managed by the Korea Centers for Disease Control and Prevention and funded by South Korea's Ministry of Health and Welfare.4) Guidelines for authors of many journals may also contain such requirements. For example, in instructions for authors of the Journal of the American Medical Association, we can find such a policy as follows. All clinical trials must be registered at an appropriate online public registry. However, the KJFM does not have such a policy for its authors. In Korea, the Bioethics and Safety Act was enacted in 2008 and was revised to reflect the rapidly changing trends in the field. It will be effective from February 2, 2013. An IRB is a committee that has been formally designated to approve, monitor, and review biomedical and behavioral research involving humans. By the revised act, all research involving subjects must be approved by the IRB. In the information for authors of the KJFM, it is stated, If the research involves life, it must comply with the ethical standards of the 1975 Helsinki Declaration (revised edition of 2004) and in principle undergo scrutiny of an independent IRB which reviews ethical issues of the experiment. But, in clinical studies, the approval of the IRB and patient's consent must be received and stated on paper. We must change our guidelines according to the revised act by changing 'clinical studies' to human subjects research. Some researchers may think that the need for a clinical trial registry and IRB approval in subjects research are obstacles in the research process; however, adhering to such guidelines will bring us closer to our goal of becoming a leading journal in the international medical community.

Publication Delay in the Korean Journal of Family Medicine

Although much improved, the time between a manuscript's submission for publication and its release still somewhat long for the Korean Journal of family medicine (KJFM). The causes of this time lag may be various in nature. Delay of author's response after peer review, delayed answer of reviewers, or delayed assignment of peer reviewers may be among the main reasons. Such publication delays may result in inflation of journal impact factors,1) or may cause publication bias.2) Therefore, efforts must be made to reduce such time lag for publication. Adherence by the authors to several principles may prevent these delays. First, the conclusion must be carefully written. If the case is for amendment of manuscripts, the main reason for amendment may be regarding the conclusion. The conclusion must be based on the results pertaining to the research hypothesis. In many cases, the conclusion may contain only for the implication of results. In that case, it must be sent to the authors. Second, information for authors must be emphasized again. Many manuscripts are still not kept properly for information for authors. This may be the main reason for author amendments. From the perspective of reviewers, quick and proper judgment in rejecting or amending must be made. It may happen that although the decision was modification of manuscripts, but the actual contents of review was close to reject of manuscripts, In addition the first review must be comprehensive, therefore not to point out in the second review the thing that was not pointed in the first review. This may be the reason for time lag. Peer review and manuscript management in KJFM also need to be addressed. In addition, rejection without a review system, review training programs, a guide for reviewers, seeking to ways to compensate reviewers, or ways to develop and maintain reviewer loyalty should be prepared3) by the editor and president of the Korean Academy of Family Medicine.

Efficacy versus Effectiveness

Archie Cochrane, British famous clinical epidemiologist, defined two concepts related to assessing healthcare interventions. Efficacy is the extent to which an intervention does more good than harm under ideal circumstances. Effectiveness assesses whether an intervention does more good than harm when provided under usual circumstances of healthcare practice.1) Research on efficacy and effectiveness has also been described as explanatory and pragmatic trials. When defining the research question, it must be considered whether one asking a pragmatic or an explanatory question. This will have important implications for study design.2) Pragmatic research assesses whether an intervention works under real-life conditions and whether it works in terms that matter to the patient. Explanatory research assesses whether an intervention works under ideal or selected conditions. The distinction between pragmatic and explanatory research is important because it will determine key methodological issues relating to patient selection, definition of the intervention and controls, use of blinding and placebos, choice of outcome measure, and type of analysis.3) Efficacy studies are frequently conducted in large tertiary care, referral settings, which tend to have more specialized clinicians and better technical equipment than primary care facilities. For effectiveness trials, settings should reflect the initial care facilities available to a diverse population with the condition of interest. Therefore, populations in primary care may be an adequate subject group for effectiveness studies.4) The Korean Journal of Family Medicine (KJFM) publishes research and reviews related to primary care, and those related to clinical and epidemiological health services. This means that the KJFM is focused primarily on the publication of effectiveness research. The distinctions between pragmatic and explanatory research pertain to patient selection, definition of the intervention and controls, and choice of outcome measure. Effectiveness research has several characteristics: 1) patient selection should reflect routine practice; 2) the intervention should be provided by normal staff with routine training; 3) the control may therefore be routine practice rather than a placebo; 4) outcome measures are usually patient centered and incorporate broad measures of health-related quality of life.5) The editorial board, reviewer, and authors must all have such an understanding to achieve the aims and scope of the KJFM.

The Korea National Health and Nutrition Examination Survey as a Primary Data Source

The Korea National Health and Nutrition Examination Survey (KNHANES) is a population-based cross-sectional survey designed to assess the health related behavior, health condition, and nutritional state of Koreans (http://knhanes.cdc.go.kr/). It was conducted as a tri-annual survey for the first 3 cycles, implemented in 1998, 2001, and 2005. Beginning with the 4th cycle of 2007, it was converted to an annual survey. The 2011 data was recently opened to the public, and is free for all researchers who want to use it. The KNHANES provides a rich source of data which are easy to access and can be quickly obtained. Its ethical problems are minimal and there are no adverse effects in conducting the study. Using the KNHANES saves time, money, and personnel that would otherwise be spent collecting data, and provides a larger and higher-quality database beyond the capacity of any one individual researcher. Further, because the study participants are representative of the Korean population, the results have external validity. Therefore, this data is helpful to young investigators. In fact, the portion of submitted articles to the Korean Journal of Family Medicine (KJFM) using the KNHANES as the primary source of data is significant. Specifically, one article in 2007, three articles in 2008, four articles in 2009, three articles in 2010, five articles in 2011, and five articles in 2012 used the KNHANES data as their primary data source, totaling 21 articles (6.2%) among 338 original articles during the previous five years. However, there are several points investigators should keep in mind when using the KNHANES data. First, the KNHANES data are open to the public and there is no systematic process to control the research topic assignment. Many researchers might investigate the same topic simultaneously, especially popular topics like obesity and metabolic syndrome. Before deciding on the study topic, a thorough search of the database like Medline, EMBASE, and the abstracts of related conferences are needed. Once the topic is decided upon, the article should be submitted as soon as possible. Otherwise someone else may publish a similar study from the same dataset before you do. Second, investigators must be familiar with the huge and complex data structure and study design of the KNHANES. Non-response and multi-stage probability sampling should be taken into account by using survey statistics to estimate the data of the whole Korean population. Despite this, lots of studies submitted to KJFM using the KNHANES do not apply sampling weight in their analysis. In such a case the estimated association might be biased and revision is required. Third, the KNHANES is a secondary data source like the Korea Youth Risk Behavior Web-based Survey and the Community Health Survey, and has the same limitations that they have.1) The main purpose of the KNHANES is to produce national statistics, not to answer a specific research question. Therefore, the particular information the investigator wants may not be collected. For these reasons, the dataset should be examined carefully to confirm that it includes the necessary data. There also exists a potential for errors or mistakes in the data, even with its rigorous documents control system. Missing data is also a problem in the KNHANES.2)

Relationship between Long Sleep Duration and Functional Capacities in Postmenopausal Women

The purpose of the present study was to examine the relationship between long sleep duration and functional capacities. We conducted a cross-sectional study at the Department of Kinanthropology at the University of Quebec at Montreal. Forty eight non-frail postmenopausal women aged between 49 to 75 years were recruited using advertisements in local papers. Body weight, body mass index, fat mass, skeletal muscle mass, number of steps per day, SF-36 total (healthy questionnaire), resting metabolic rate, total energy intake, sleep duration, knee extensor strength (dynamometer), chair stand test and balance opened eyes test were measured. WE FOUND A SIGNIFICANT NEGATIVE CORRELATION BETWEEN HOURS OF SLEEP AND FUNCTIONAL CAPACITY: chair stand test (r = -0.33, p = 0.02), balance opened eyes test (r = -0.45, p = 0.001), muscle strength (r = -0.43, p = 0.002) and skeletal muscle mass (r = -0.39, p = 0.007). In addition, long sleepers (> 9 h) had significantly lower values for skeletal muscle mass (p = 0.03), muscle strength (p = 0.01), chair stand test (p = 0.03), and balance opened eyes test (p = 0.001). Finally, linear regression analysis showed that sleep duration was an independent predictor of the chair stand test (p = 0.024), balance opened eyes test (p = 0.001), and muscle strength (p = 0.035) in our cohort. Long sleepers were associated with lower functional capacities in our cohort of sedentary postmenopausal women.

Statistical Trends in Family Medicine Journals

BackgroundThis study proposed a desirable direction for the future development of the Korean Journal of Family Medicine (KJFM) by comparing with the overseas SCI journals, Family Medicine (FM) and The Journal of Family Practice (JFP) based on the statistical viewpoints.MethodsAll of the original articles published in KJFM from January 1981 to June 2011, FM from January 1998 to June 2011, and JFP from January 1978 to June 2011, were reviewed and compared in terms of content, data size, research design, and statistical method.ResultsOf 3,226 total original articles, KJFM published 1,549, FM 322, and JFP 1,355, respectively. Both JFP and KJFM mainly focused on biomedical topics (67.2% and 61.7%), while FM focused on education (55.9%). Most of the studies in three journals used the data size of between 100 to 300 cases. The most frequently used research design was cross-sectional, FM 66.8%, JFP 58.4%, and KJFM 72.4%, respectively. The statistical methods in KJFM were gradually diversified.ConclusionThe quality of the original articles in KJFM has been improved over the years, but still has conducted based on the relatively weak research designs. Under the circumstances that the higher ranked SCI journals demand the prospective design and large size of data, and most researchers in Korea could not use the large scaled prospective data, we need to collaborate to accumulate the small sized data sets and try to make a registry. More refined statistical method such as a propensity score matching analysis for retrospective data could be an alternative.

Misinterpreting Odds Ratio in the Articles Published in Korean Journal of Family Medicine

BackgroundIn reporting results of case-control studies, odds ratios are useful methods of reporting findings. However, odds ratios are often misinterpreted in the literature and by general readers.MethodsWe searched all original articles which were published in the Korean Journal of Family Medicine from 1980 to May 2011 and identified those that report "odds ratios." Misinterpretation of odds ratios as relative risks has been identified. Estimated risk ratios were calculated when possible and compared with odds ratios.ResultsOne hundred and twenty-eight articles using odds ratios were identified. Among those, 122 articles were analyzed for the frequency of misinterpretation of odds ratios as relative risks. Twenty-two reports out of these 122 articles misinterpreted odds ratios as relative risks. The percentage of misinterpreting reports decreased over years. Seventy-seven reports were analyzed to compare the estimated risk ratios with odds ratios. In most of these articles, odds ratios were greater than estimated risk ratios, 60% of which had larger than 20% standardized differences.ConclusionIn reports published in the Korean Journal of Family Medicine, odds ratios are frequently used. They were misinterpreted in part of the reports, although decreasing trends over years were observed.

Efforts for SCI Listing

Since June 2012, the Korean Journal of Family Medicine (KJFM) has been listed on PubMed Central (PMC). PMC is a free full-text archive of biomedical and life sciences journals at the US National Institutes of Health's National Library of Medicine.1) Although PMC listing does not imply Medline listing, KJFM is included in the PubMed search, and it may result in an increase in citation of KJFM articles and increase in foreign researchers' manuscript submission. KJFM also has been listed on the Scopus since December 2011. Scopus, officially named SciVerse Scopus, is a bibliographic database containing abstracts and citations for academic journal articles. It covers nearly 18,000 titles from over 5,000 international publishers, including coverage of 16,500 peer-reviewed journals in the scientific, technical, medical, and social sciences. It is owned by Elsevier and is available online by subscription.2)

The Quality of Reporting of Cohort, Case-Control Studies in the Korean Journal of Family Medicine

BackgroundThe Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement was developed to improve the reporting of observational studies. We aimed to evaluate the quality of reporting in cohort studies and case-control studies among observational studies published in the Korean Journal of Family Medicine.MethodsWe searched for cohort studies and case-control studies published as original articles in the Journal of the Korean Academy of Family Medicine during the period January 1992 through December 2009. The main outcome measures were the number and proportion of cohort studies and case-control studies that reported each of 22 checklist items of STROBE.ResultsWe identified a total of 84 articles, of which 46 articles were cohort studies and 38 were case-control studies. Concerning methods, study designs (10%), bias (13%), study size (0%), statistical methods (12-c and 12-e items, 0%; 12-d item, cohort study, 6%) have been poorly reported. Of results, participants (5-6%), descriptive data (14-b item, 5%), and funding (1%) among other information have been poorly reported.ConclusionThe degree of adherence the STROBE recommendations was relatively low in cohort studies and case-control studies published in the Korean Journal of Family Medicine. An effort to improve the reporting of observational studies by application and recommendation of the STROBE statement is required.

Rate of Missing Socioeconomic Factors in the 4th KNHANES

This study is to assess how missing values in socioeconomic status (SES) variables were handled in the Korean Journal of Family Medicine (KJFM) article using the Korea National Health and Nutrition Examination Survey (KNHANES) data and to estimate the rate of missing SES variables from the 4th KNHANES. We searched all original articles published in the KJFM from 2007 to 2011 and identified those that used KNHANES as their primary source of data. None of the 11 articles which presented KNHANES SES variables took into account of omitions in the analysis. The estimated rate of missing data on education, household income, marital status, and occupation data of the 4th KNHANES was 0.3 (0.05)%, 2.7 (0.2)%, 0.5 (0.1)%, and 9.4 (0.9)%, respectively. When all four variables were used simultaneously, the rates increased to 11.8 (0.9)%. Respondents with missing household income tended to be older (P < 0.001), less educated (P < 0.001), and more likely to be unemployed (P < 0.001), and widowed (P < 0.001). A similar relationship was shown for missing occupation data. Omissions in SES variables in KNHANES were related to certain characteristics of study participants. Researchers using KNHANES data should keep in mind the possible bias which can be introduced by missing SES values.

Double Submission, Double Publication

Double can be defined as publication of a paper that overlaps substantially with one already published in print or electronic media.1) The practice of duplicate publications is considered unethical because it exaggerates findings, wastes times of editors, peer reviewers, and readers, and also breaks integrity of science.2) Double can be started with double (or multiple) submission. Double submission can be defined as the submission of a paper to a journal after that is under concurrent review by another Authors should only submit original work that has neither appeared elsewhere for publication, nor which was under review for another refereed publication. Guidelines for authors of many journals contain prohibition of double submission. For example, in instructions for author of Care, we can find such a policy as follows. Diabetes Care publishes only material that has not been published previously (either in print or electronically) and is not under consideration for elsewhere. Recently we found a case of double submission. In course of review, a reviewer of Korean Journal of Family Medicine (KJFM) found that manuscript was already published in a foreign Science Citation Index (SCI) journal. Double submission is also considered unethical because it may result in double publication. Double submission can take place for many reasons: author may not know that double submission is unethical, may be a junior researcher, or may not want to delay publication. Whatever reason, double submission is a form of publishing misconduct. For previous case, we will contact corresponding author, will state that submitted work has already been published elsewhere, and will ask for explanation about that. If author gives a sufficient and reasonable explanation, we reject submission without penalties. However, if author does not respond, explanation is unsatisfactory, or author admits guilt, we will reject submission with penalties, for example, sending a letter of warning, imposing a ban on submissions to KJFM for one or two years, or informing author's superior about misconduct. Double submission remains one of least well understood forms of publishing misconduct, and has significant negative impact on research community. Establishing clear guidelines and training junior researchers sufficiently can help reduce problem of double submission.

Comments on Statistical Errors for May Issue 2012

In this section, we would like to explain the properties of the relative risk (RR) and odds ratio (OR) which appeared in the article titled, Misinterpreting odds ratio in the articles published in the Korean Journal of Family Medicine, published in March 2012 by Kim et al.,1) and the relationship between both measures in prospective and retrospective studies.

Systematic Review Research in Family Medicine

A systematic review can be defined as a investigation that focuses on a specific question and uses explicit, prespecified scientific methods to identify, select, assess, and summarize the findings of similar but separate studies.1) Systematic reviews aim to minimize bias by using explicit and systematic methods. To reach such a goal, systematic reviews seek to collate all evidence that fits pre-specified eligibility criteria in order to address a specific research question. The key characteristics of a systematic review are 1) a clearly stated set of objectives with pre-defined eligibility criteria for studies; 2) explicit, reproducible methodology; 3) a systematic search that attempts to identify all studies that would meet the eligibility criteria; 4) an assessment of the validity of the findings of the included studies, for example through the assessment of risk of bias; and 5) a systematic presentation, and synthesis, of the characteristics and findings of the included studies.2) The number of systematic reviews is growing rapidly. In PubMed, the number of systematic reviews indexed increased from 2,167 in 2005 to 5,573 in 2011. However, the number of systematic reviews indexed in KoreaMed is less than 100, and the number published in the Korean Journal of Family Medicine or the Journal of Korean Academy of Family Medicine is less than 10. So it can be said that systematic review research had been increasing in foreign countries, but not in Korea, nor in family medicine in Korea. As a research methodology in family medicine field, systematic review has many advantages. First, the citation impact of systematic review is more than other study designs.3) Second, it is easier to be published in a Science Citation Index journal than other study design. Third, it does not require institutional review board approval for research. However, in order to be a trustworthy and reliable systematic review, the quality of the systematic review process must be improved. Core standards for systematic review may include 1) writing the review protocol, 2) comprehensive literature search, 3) duplicate study selection and data extraction, 4) assessment of scientific quality of the included studies, 5) appropriate meta-analysis methodology, and 6) reporting according to guidelines (preferred reporting items for systematic reviews and meta-analyses4) checklist). Well-conducted systematic review will help make clear what is known and not known about the potential benefits and harms of interventions. Thus, systematic reviews are essential for clinicians who strive to integrate research findings into their daily practices. They must, however, meet certain standards in order to be of such use.

Quality Assessment of Non-Randomized Studies in the Korean Journal of Family Medicine

Background: Since the Korean Journal of Family Medicine (KJFM) started publishing in 1980, randomized controlled trials (RCTs) and non-randomized controlled studies (NRSs) consistently have increased in quality and quantity. Although there have been several studies on the quality assessment of RCTs in Korea, there has been no study on quality assessment of NRSs. Thus, this study evaluated NRS in the KJFM to assess the quantity and quality. Methods: Upon extracting NRSs for assessing the intervention effects from all the articles published in the KJFM from 1980 to 2006, assessments were made on methodological index for non-randomized studies (MINORS). Also, the analysis were made upon the proportion of NRSs within original articles according to two categories (comparative study, noncomparative study). The mean scores by research methods and years, and total scores and mean scores of yearly research methods were analyzed. Results: A total of 34 trials on NRSs were selected. In 1980s, 0.65% of the total selected original articles, in 1990s, 1.54%, and in 2000s 5.11% were NRSs. According to the research designs, the mean scores of MINORS were before and after study 8.5, interrupted Time Series 9.7 (out of 16), controlled before and after 13.5, quasi randomized trial 12.6, and non randomized trial 13 (out of 24). Before and after design was the most frequently used (55.9%). Conclusion: Although NRSs consistently increased in quantity, the assessed mean scores were low and most articles used before and after design. Thus, there should be studied using appropriate research methods in the future.