My Research

The future is learning – Selected publications

Question: What is the relative effectiveness of nicotine-containing electronic cigarettes (ECs) and varenicline as smoking cessation aids?

Findings: In this randomized, double-blinded, double-dummy, placebo-controlled trial including 458 adults with moderate to heavy dependence on nicotine and who were motivated to quit smoking traditional cigarettes, nicotine-containing ECs and varenicline were both effective in helping them to stop smoking for up to six months.

Meaning: The results of this randomized clinical trial indicated that nicotine-containing ECs seems to be an effective option as smoking cessation treatment for adults who smoke traditional cigarettes.

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Multivariable statistical analysis involves the dichotomy of modeling and predicting. Yet, in clinical medicine, epidemiology, and health care research, the main goal is to understand, rather than to predict. Physicians are more eager to understand the phenomenon of a severe disease and to learn how to help a patient to survive as long as possible, than to be able to predict the survival time. For epidemiologists, knowing how to reduce the prevalence or incidence of a disease in a population is more important than predicting who will develop a disease. For clinicians and subject-specific researchers, the point of looking at health data is often to intervene to change the expected outcomes.

Artificial intelligence (AI) methods, including machine learning (ML), deep learning (DL) and random forests, have come to show promise in the field of medicine, and these methods can develop effective diagnostic and predictive tools to identify various diseases. However, prediction methods suffer from the “black box” problem: inputs are fed to the algorithm and an output emerges, but it is not entirely clear which variables were identified, or how they contributed to the final output. Models do not provide an effect size index that is familiar to medical researchers and that helps them evaluate the effect of specific explanatory variables.

The application and interpretability of predictive data analysis methods in medicine is discussed in this paper.

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The lack of consistent presentation of results in published studies on the association between a quantitative explanatory variable and a quantitative dependent variable has been a long-term issue in evaluating the reported findings. Studies are analyzed and reported in a variety of ways. The main purpose of this review is to illustrate the procedures in summarizing and synthesizing research results from multivariate models with a quantitative outcome variable.

The review summarizes the application of the standardized regression coefficient as an effect size index in the context of meta-analysis and describe how it can be estimated and converted from data presented in original research articles.

An example of synthesis is provided using research articles on the association between childhood body mass index and carotid intima-media thickness in adult life. Finally, the paper shares practical recommendations for meta-analysts wanting to use the standardized regression coefficient in pooling findings.

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The increased use of social media in dentistry is associated with advantages and disadvantages. A new form of professionalism, “e-professionalism,” has emerged. It includes an online persona and online information in any format that displays cues to professional identity, attitudes, and behaviors. The objective was to explore the perceptions of Malaysian and Finnish dental students on e-professionalism.

A survey of 613 Malaysian and Finnish students was performed. The main variables assessed were posting of objectionable or inappropriate content among students, attitudes towards unprofessional online content, perceived online presence, contacts with patients and faculty members on social media and concerns about social media use.

The prevalence of posting clearly unprofessional content was not high among dental students. Revealing information of patients was most common content of clear unprofessionalism. Students from Malaysia contacted patients and faculty members more actively in social media than students in Finland (73.6% of students in Malaysia and 11.8% in Finland had invited faculty members to be ”friends”). Malaysian students were more concerned and more likely to react to inappropriate content on social media. Attitude of dental students towards social media use in dentistry were very positive in both countries. Students agreed that guiding patients online is a new responsibility for dentists in the digital age” (86.4% of students in Malaysia and 73.4% in Finland).

The findings indicate the existence of both benefits and dangers of social media on e-professionalism among students. There is a need to include robust digital professionalism awareness training for students.

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Social media use among students has infiltrated into dental education and offers benefits but may also cause problems. The aim of this study was to explore and compare current social media usage among dental undergraduate students from two countries—Malaysia and Finland. A self-administered structured online questionnaire was used.

WhatsApp, YouTube, Instagram, Facebook and Snapchat were the services that were most familiar to the respondents from both countries. There were differences between the students from the two countries among the most preferred platforms. The most frequently used applications were WhatsApp (91.1% of students in Malaysia and 96.1% in Finland used it very frequently) and Instagram (74.3% of students in Malaysia and 70.0% in Finland used it very frequently). Students in Malaysia spent significantly more hours per week using the platforms as study tools than students in Finland. Over 80% of the Finnish dental students reported that lack of knowledge was not an issue in social media usage, while 85% of Malaysian students felt that lack of knowledge prevented them from using social media platforms frequently.

The findings offer evidence that dental students used social media extensively.

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Proper peer review and quality of published articles are often regarded as signs of reliable scientific journals. The aim of this study was to compare whether the quality of statistical reporting and data presentation differs among articles published in ‘predatory dental journals’ and in other dental journals. We evaluated 50 articles published in ‘predatory open access (OA) journals’ and 100 clinical trials published in legitimate dental journals between 2019 and 2020. The quality of statistical reporting and data presentation of each paper was assessed on a scale from 0 (poor) to 10 (high). The mean (SD) quality score of the statistical reporting and data presentation was 2.5 (1.4) for the predatory OA journals, 4.8 (1.8) for the legitimate OA journals, and 5.6 (1.8) for the more visible dental journals. The mean values differed significantly (p < 0.001). The quality of statistical reporting of clinical studies published in predatory journals was found to be lower than in open access and highly cited journals. This difference in quality is a wake-up call to consume study results critically. Poor statistical reporting indicates wider general lower quality in publications where the authors and journals are less likely to be critiqued by peer review.

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The science of statistics contributes to the development and application of tools for the design, analysis, and interpretation of empirical medical studies. The development of new statistical tools for medical applications depends on the innovative use of statistical inference theory, good understanding of clinical and epidemiological research questions and an understanding of the importance of statistical software. First, statisticians develop a method in response to a need felt in a particular field of the health sciences, after which the new method is disseminated in the form of presentations, reports, and publications. It is also necessary to develop tools for implementing the method: software and manuals. From this point onwards the extent to which the procedure is adopted will depend on its usefulness. The broader introduction and acceptance of a new analysis method (as useful as the method might be) into medical and health care publications seems to require the method being incorporated into the standard statistical packages generally used by researchers. In addition, if readers do not understand the mathematics or reporting style, or if the conclusions have been drawn on the basis of advanced mathematics or computationally complex procedures not visible in the data (tables or graphs) presented, then clinicians may not be convinced of the results. The lead time from the description of a new technique to its entering into the practice of medical investigators is long.

Unsustainable promises and unfulfillable expectations should be avoided in the context of data mining and machine learning. The broader introduction and expansion of a new analysis method to medical publication seems to require that the method helps to solve a data analysis problem, where basic statistical methods have not been useful or applicable. Simpler classical approaches can often provide elegant and sufficient answers to important questions.

This special issue on Medical Informatics and Data Analysis was an opportunity for the scientific community to present research on the application and complexity of data analytical methods, and to give insight into new challenges in biostatistics, epidemiology health sciences, dentistry and clinical medicine. The 13 contributed articles belong to four broad groups: (i) basic statistical methods, (ii) data-oriented practical approaches, (iii) complex machine learning and deep learning predictive algorithms, (iv) medical informatics.

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Background: A fundamental skill in education includes the ability to search for, evaluate, and synthesize information, and this cannot be underestimated in dental education. The aim of this study was to assess how dental students from Malaysia and Finland acquire scientific information and to compare their information retrieval skills.
Methods: Fourth and fifth-year dental students from Malaysia and Finland were invited to participate. A self-administered structured questionnaire including items about the use of information sources, subjective assessment of literature retrieval skills and knowledge was used.
Results: A total of 226 dental students participated in the survey: 131 from Malaysia and 95 from Finland. In both countries, the highest interest for data retrieval among students was found in the oral surgery specialty. The three most used sources of information among Malaysian students were personal lecture notes, dental textbooks, and colleagues; while Finnish students used colleagues, lecture notes, and current clinical guidelines. Students’ knowledge of evidence-based practice was inadequate in both student groups. Though the majority of participants reported that they had good or passable skills in literature retrieval, more students from Finland judged themselves to have at least good skills compared to those from Malaysia.
Conclusion: Dental education in both countries includes information retrieval studies and mandatory research projects. However, students did not often use those sources that are considered essential in evidence-based dentistry. Universities should further develop educational and training interventions that guide students to use knowledge resources more effectively for critically appraising scientific evidence.

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Background: Data analysis methods have become an essential part of empirical research papers, especially in health sciences and medical research. It has previously been reported that a noteworthy percentage of articles have flaws in their statistical reporting. Reporting problems have been a long-term issue, and despite continued efforts to improve the situation, improvements have been far from satisfactory. One explanation is an inadequate assessment of statistical reporting during peer review. This communication proposes a short instrument to assess the quality of data analysis reporting in manuscripts and published papers.
Method: A checklist-type instrument was developed by selecting and refining items from previous reports about the quality of statistical reporting in medical journals and from published guidelines for reporting and data presentation. Items were pretested and modified during pilot studies. A total of 160 original medical research articles that were published in 4 journals were evaluated to test the instrument. Interrater and intrarater agreements were examined by comparing quality scores assigned to 40 articles published in a psychiatric journal.
Results: The data analysis reporting test consists of nine questions that assess the quality of health research from a reader’s perspective. The composed scale has a total score ranging from 0 to 10 and discriminated between journals and study designs. A high score suggested that an article had a good presentation of findings in tables and figures and that the description of analysis methods was helpful to readers. Interrater and intrarater agreements were high.
Conclusion: An applicable checklist for quickly testing the statistical reporting quality of manuscripts and published research papers was developed. This instrument aims to improve the quality of empirical research in scientific fields where statistical methods play an important role.

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Data analysis methods play an important role in respiratory research. We evaluated the application and complexity of data analytical methods in high impact respiratory journals and compared the statistical reporting in these respiratory articles with reports published in other eminent medical journals.

This study involved a total of 160 papers published in 2015 in European Respiratory Journal, American Journal of Respiratory and Critical Care Medicine, Chest and Thorax; and 680 papers published between 2007 – 2015 in other medical journals including the Lancet and New England Journal of Medicine (NEJM). We manually reviewed the articles to determine the way in which they reported the methods applied in data analysis.

The statistical intensity in the respiratory journals was equal to that in eminent medical journals. Traditional ways of testing statistical significance were widely used in respiratory articles. Statistical procedures were not always described in sufficient detail, and the prominent respiratory journals did not display different profiles with respect to their statistical content.

Readers of the prominent respiratory journals need to possess a substantial level of statistical expertise if they wish to critically evaluate the design, methodology, data analysis, and interpretation of the findings published in these journals.

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Background: There is widespread evidence that statistical methods play an important role in original research articles, especially in medical research. The evaluation of statistical methods and reporting in journals suffers from a lack of standardized methods for assessing the use of statistics. The objective of this study was to develop and evaluate an instrument to assess the statistical intensity in research articles in a standardized way.

Methods: A checklist-type measure scale was developed by selecting and refining items from previous reports about the statistical contents of medical journal articles and from published guidelines for statistical reporting. A total of 840 original medical research articles that were published between 2007-2015 in 16 journals were evaluated to test the scoring instrument. The total sum of all items was used to assess the intensity between sub-fields and journals. Inter-rater agreement was examined using a random sample of 40 articles.  Four raters read and evaluated the selected articles using the developed instrument.

Results: The scale consisted of 66 items. The total summary score adequately discriminated between research articles according to their study design characteristics. The new instrument could also discriminate between journals according to their statistical intensity. The inter-observer agreement measured by the ICC was 0.88 between all four raters. Individual item analysis showed very high agreement between the rater pairs, the percentage agreement ranged from 91.7% to 95.2%.

Conclusions: A reliable and applicable instrument for evaluating the statistical intensity in research papers was developed. It is a helpful tool for comparing the statistical intensity between sub-fields and journals. The novel instrument may be applied in manuscript peer review to identify papers in need of additional statistical review.

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Background: One of the core skills of competent dentist is the ability to search and analyse high-quality evidence. Problems in understanding the basic aspects of knowledge-based information may impede its implementation into clinical practice. We examined how Finnish dental students acquire scientific information and how familiar they are with methods for evaluating scientific evidence related to clinical questions.

Methods: All fifth-year dental students (N=120) at the three universities in Finland received a self-administered questionnaire.  

Results: The three most commonly used sources of information were colleagues, the commercial Health Gate Portal for dental practitioners and personal lecture notes. Although students rarely read scientific journals, they did find that they possess at least passable or even good skills in literature retrieval. Three questions related to the appraisal of evidence in dentistry revealed that students’ knowledge of evidence-based dentistry was inadequate to critically evaluate clinical research findings.

Conclusion: Most students seem to lack knowledge of key methodological evidence-based terms. The present curricula in dental schools fail to encourage the students to search and acquire knowledge wider than their patients themselves do. Universities have the responsibility to teach dentists various methods of critical appraisal to cope with scientific information.

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Hammaslääkärit kohtaavat merkittävän haasteen pohtiessaan tieteellistä näyttöä ja mihin uusiin tutkimusmenetelmiin kannattaisi tutustua. Usein heidän tarvitsee täydentää erityisesti tilastollisten menetelmien osaamistaan. Yksi lähestymistapa on keskittyä niihin tilastollisiin menetelmiin, joita tiedelehtien lukijat tarvitsevat pystyäkseen seuraamaan alansa kirjallisuutta. Selvitimme tilastollisten menetelmien käyttöä hammaslääketieteen lehdissä ja vertasimme sitä lääketieteen yleislehtiin. Pohdimme, mitä tilastollisia menetelmiä hammaslääketieteen lehtien lukijan tulee tällä hetkellä tuntea. Esittelemme niitä valmiuksia, joiden avulla lukija pystyy hyvin arvioimaan lähes kaikki tuoreimmat hammaslääketieteen tieteelliset artikkelit ja parhaiten hyödyntämään raportoituja tutkimustuloksia.

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Lääketieteellisissä julkaisuissa tutkimustuloksista ja uusista löydöksistä viestitään yleensä erilaisilla tilastollisilla esityksillä. Tilastomenetelmillä on siten merkittävä osuus lääketieteen tieteellisessä viestinnässä. Lehtien lukijoista valtaosa on saanut opiskeluaikanaan vain suppean koulutuksen lääketieteen tilastollisiin menetelmiin. Pystyäkseen lukemaan ja ymmärtämään lehtien tutkimustuloksia heidän tulee usein täydentää tilastollista osaamistaan. Erityisesti tieteellisen jatkokoulutuksen rooli on tässä huomattava. Minkä menetelmän perusteisiin ja rajoitteisiin opinnoissa kannattaisi erityisesti tutustua? Vieläkö pärjää t-testillä ja khiin neliö -testillä?

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Background: A major problem in evaluating and reviewing the published findings of studies on the association between a quantitative explanatory variable and a quantitative dependent variable is that the results are analysed and reported in many different ways. To achieve an effective review of different studies, a consistent presentation of the results is necessary. This paper aims to exemplify
the main topics related to summarising and pooling research findings from multivariable models with a quantitative response variable.
Methods: We outline the complexities involved in synthesising associations. We describe a method by which it is possible to transform the findings into a common effect size index which is based on standardised regression coefficients. To describe the approach we searched original research articles published before January 2012 for findings of the relationship between polychlorinated biphenyls (PCBs) and birth weight of new-borns. Studies with maternal PCB measurements and birth weight as a continuous variable were included.
Results: The evaluation of 24 included articles reveled that there was variation in variable measurement methods, transformations, descriptive statistics and inference methods. Research syntheses were performed summarizing regression coefficients to estimate the effect of PCBs on birth weight. A birth weight decline related to increase in PCB level was found.
Conclusions: The proposed method can be useful in quantitatively reviewing published studies when different exposure measurement methods are used or differential control of potential confounding factors is not an issue.

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Background: In some parts of the northwest Russia, Murmansk region, high exposures to heavy mining and refining industrial air pollution, especially sulphur dioxide, have been documented.

Objective: Our aim was to evaluate whether living in the mining area would be an independent risk factor of the respiratory symptoms.

Design: A cross-sectional survey of 200 Murmansk region adult citizens was performed. The main outcome variable was prolonged cough with sputum production that fulfilled the criteria of chronic bronchitis.

Results: Of the 200 participants, 53 (26.5%) stated that they had experienced chronic cough with phlegm during the last 2 years. The prevalence was higher among those subjects living in the mining area with its high pollution compared to those living outside this region (35% vs. 18%). Multivariable regression model confirmed that the risk for the chronic cough with sputum production was elevated in a statistical significant manner in the mining and refining area (adjusted OR 2.16, 95% CI 1.07–4.35) after adjustment for smoking status, age and sex.

Conclusions: The increased level of sulphur dioxide emitted during nickel mining and refining may explain these adverse health effects. This information is important for medical authorities when they make recommendations and issue guidelines regarding the relationship between environmental pollution and health outcomes.

Objective: Citations by other researchers are important in the dissemination of research findings. We aimed to investigate whether preferential citation of statistically significant articles exists in the psychiatric literature.
Study design and settings: We analyzed all original research papers published in 1996 in four psychiatric journals. Using a standardized questionnaire, from each paper, we extracted the primary outcome and its statistical significance. The number of citations, excluding authors’ ‘‘self-citations,’’ received by April 2005 was obtained. Regression analysis was used to relate citation frequency to statistical significance, adjusting for confounders.
Results: Of 448 extracted papers, 368 used statistical significance testing and 287 (77.8%) reported P < 0.05. The median number of citations for papers reporting ‘‘significant’’ and ‘‘nonsignificant’’ results was 33 vs. 16. After adjustment for journal, study design, reporting quality, whether outcome confirmed previous findings and study size, the ratio of the number of citations per article for articles reporting ‘‘P < 0.05’’ on the primary outcome to those reporting ‘‘P > 0.05’’ was 1.63 (95% confidence interval [CI]: 1.32, 2.02, P < 0.001).
Conclusion: Authors cite studies based on their P-value rather than intrinsic scientific merit. This practice skews the research evidence. Systematic study registration and inclusion in meta-analysis should be encouraged.

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Background: Teaching the principles of scientific research in a comprehensive way is important at medical and dental schools. In many countries medical and dental training is not complete until the candidate has presented a diploma thesis. The objective of this study was to evaluate the nature, quality, publication pattern and visibility of Finnish medical diploma theses.

Methods: A total of 256 diploma theses presented at the University of Oulu from 2001 to 2003 were analysed. Using a standardised questionnaire, we extracted several characteristics from each thesis. We used the name of the student to assess whether the thesis resulted in a scientific publication indexed in medical article databases. The number of citations received by each published thesis was also recorded.

Results: A high proportion of the theses (69.5%) were essentially statistical in character, often combined with an extensive literature review or the development of a laboratory method. Most of them were supervised by clinical departments (55.9%). Only 61 theses (23.8%) had been published in indexed scientific journals. Theses in the fields of biomedicine and diagnostics were published in more widely cited journals. The median number of citations received per year was 2.7 and the range from 0 to 14.7.

Conclusion: The theses were seldom written according to the principles of scientific communication and the proportion of actually published was small. The visibility of these theses and their dissemination to the scientific community should be improved.

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Background: Citation counts are often regarded as a measure of the utilization and contribution of published articles. The objective of this study is to assess whether statistical reporting and statistical errors in the analysis of the primary outcome are associated with the number of citations received.
Methods: We evaluated all original research articles published in 1996 in four psychiatric journals. The statistical and reporting quality of each paper was assessed and the number of citations received up to 2005 was obtained from the Web of Science database. We then examined whether the number of citations was associated with the quality of the statistical analysis and reporting.
Results: A total of 448 research papers were included in the citation analysis. Unclear or inadequate reporting of the research question and primary outcome were not statistically significantly associated with the citation counts. After adjusting for journal, extended description of statistical procedures had a positive effect on the number of citations received. Inappropriate statistical analysis did not affect the number of citations received. Adequate reporting of the primary research question, statistical methods and primary findings were all associated with the journal visibility and prestige.
Conclusion: In this cohort of published research, measures of reporting quality and appropriate statistical analysis were not associated with the number of citations. The journal in which a study is published appears to be as important as the statistical reporting quality in ensuring dissemination of published medical science.

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