Person: ERCAN, İLKER
Loading...
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
ERCAN
First Name
İLKER
Name
43 results
Search Results
Now showing 1 - 10 of 43
Publication Evaluating the sensitive question methods; Recommended Uludag adjustment for the crosswise model(Taylor, 2021-10-27) Ahmadian, Robab; Ercan, İlker; Ahmadian, Robab; ERCAN, İLKER; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Temel Tıp Bilimleri/Biyoistatistik; 0000-0003-1550-639X; 0000-0002-2382-290X; AAE-5602-2019; ABF-2367-2020Sensitive questions are frequently asked in medical, psychological, and sociological research. In the social science literature, it is widely accepted that when respondents are asked such questions, social desirability bias affects survey research. Different methods in the literature aimed to reduce measurement errors such as social desirability bias and increase the reliability of participants' answers. These methods address the problem to increase the effectiveness of predictions by using indirect questioning techniques. The sensitive question methods evaluated in this study are randomized response technique, grouped answer method, unmatched-count technique, and crosswise model. These methods were evaluated with a comprehensive simulation study. The performances of the methods were evaluated according to the sample size and the sensitive issue prevalence in the hypothetical population. In the second part, in order to reduce the small sample size and low prevalence effect of the crosswise model, the Uludag correction of the crosswise model was proposed in the study. As a result, the crosswise model performs quite well compared to the other methods. In the use of the crosswise model, it is recommended to use the Uludag correction of the model proposed in this study in cases where low prevalence and small samples are studied.Publication Ensemble of effect size methods based on meta fuzzy functions(Pergamon-elsevier Science Ltd, 2023-01-05) Tak, Aysegül Yabacı; Ercan, İlker; ERCAN, İLKER; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; 0000-0002-2382-290XMany methods are used in the literature to determine the effect size (ES) for two independent groups. Many of these methods yield consistent results under the assumptions of normality of data and homogeneity of variances. However, not every dataset can provide these assumptions. In order to overcome the limitations mentioned, this study proposes the use of meta fuzzy effect size functions (MFESF). The MFESF weights six ES methods (Cohen's d, Hedge's g, and Glass' delta, Cliff's delta, Vargha and Delaney A and Glass' rank-biserial correlation) used for two independent groups according to their performances and provides better outcomes, regardless of assumptions. The MFESF method uses the fuzzy c-means (FCM) clustering algorithm to combine the selected ES methods. In this study, MFESF is evaluated by using generated datasets based on normal and non-normal distribution for six reference values. In addition, the performance of MFESF is evaluated by using real datasets with normal and non-normal distributions. As a result, the MFESF performed the best with the lowest mean absolute percentage error (MAPE) compared to the individual ES methods for all datasets.Publication A retrospective epidemiological study of 385 burn patients hospitalized during 6 years in bursa(Springer, 2005-09-01) Özbek, Serhat; KAHVECİ, RAMAZAN; ÖZGENEL, GÜZİN YEŞİM; ÖZBEK, SERHAT; Özcan, Mesut; AKIN, SELÇUK; Akın, Selçuk; ERCAN, İLKER; Ercan, İlker; Karaca, Kemal; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Plastik ve Rekonstruktif Cerrahi Anabilim Dalı.; 0000-0002-2382-290X; AAG-4626-2019; AAH-5064-2021; AAH-5441-2021A retrospective analysis of 385 consecutive admissions to a regional burns unit in a period of 6 years is presented. The majority were flame burns, followed by scalds. The male to female ratio was 3: 1. More than half of the patients were adults (more than the age of 16 years) and most of the injuries occurred at home. In the group of patients under 2 years of age, scalds were the leading cause of burns and among them hot tea spill was the most common reason. Many of the electrical burns occurred at the workplace and at home were resulted from inappropriate close location of high voltage lines to constructions and houses, and inappropriate use of paint thinner was found to be an important cause for flame burns occurred at the work place. The mean hospitalization time was 27.1 days and the overall mortality rate was 14% (n=54). In this paper, regional characteristics of some etiologic factors, together with some descriptive analysis in burn injury and some preventive measures are presented.Publication Examining cronbach alpha, theta, omega reliability coefficients according to the sample size(Wayne State Univ Press, 2007-05-01) Ercan, İlker; Yazıcı, Berna; Sığırlı, Deniz; Ediz, Bülent; Kan, İsmet; ERCAN, İLKER; SIĞIRLI, DENİZ; Ediz, Bülent; Kan, İsmet; Uludağ Üniversitesi/Biyostat Bölümü; 0000-0002-2382-290X; ABF-2367-2020; AAA-7472-2021; EXB-2757-2022; FCI-0480-2022Differentiations according to the sample size of different reliability coefficients are examined. It is concluded that the estimates obtained by Cronbach alpha and teta coefficients are not related with the sample size, even the estimates obtained from the small samples can represent the population parameter. However, the Omega coefficient requires large sample sizes.Publication Examining the variations in the results of the hotelling T² test in case of changing baseline landmarks in the bookstein coordinates(Springer Heidelberg, 2015-06-01) Ercan, İlker; Sığırlı, Deniz; Özkaya, Güven; ERCAN, İLKER; SIĞIRLI, DENİZ; ÖZKAYA, GÜVEN; Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; 0000-0002-2382-290X; 0000-0003-0297-846X; AAA-7472-2021; A-4421-2016; ABF-2367-2020In many biological and biomedical investigations, the most effective way to analyze the forms of whole biological organs or organisms is by recording geometric locations of landmark points. If we want to compare shapes, then individuals should be translated, rotated and scaled in such a way that all of the individuals lie in a standard position and are centered. Bookstein conducted this process by choosing two landmarks as reference landmarks. Each individual is translated, rotated and scaled according to these reference landmarks. The aim of the present study was to examine the change in the p values in the case of choosing different baseline landmarks when performing the Hotelling T (2) test, which is commonly used when comparing two sample shape configurations based on Bookstein coordinates. For this purpose, the changes in the p values were investigated in shape configurations that are composed of a different number of landmarks by taking all of the possible paired landmark combinations at different variance levels and sample sizes. As a result of the present study, it was observed that with the increase in the landmark number, the number of possible baseline landmark combinations also increases and, for this reason, a substantial number of variations occur in the p values. Therefore, it is an important to decide which landmarks should be taken as reference landmarks when using the Bookstein coordinates.Publication Examining the efficiency of models using tangent coordinates or principal component scores in allometry studies(Springer Heidelberg, 2015-09-01) Sığırlı, Deniz; Ercan, İlker; SIĞIRLI, DENİZ; ERCAN, İLKER; Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; 0000-0002-2382-290X; AAA-7472-2021; ABF-2367-2020Most of the studies in medical and biological sciences are related to the examination of geometrical properties of an organ or organism. Growth and allometry studies are important in the way of investigating the effects of diseases and the environmental factors effects on the structure of the organ or organism. Thus, statistical shape analysis has recently become more important in the medical and biological sciences. Shape is all geometrical information that remains when location, scale and rotational effects are removed from an object. Allometry, which is a relationship between size and shape, plays an important role in the development of statistical shape analysis. The aim of the present study was to compare two different models for allometry which includes tangent coordinates and principal component scores of tangent coordinates as dependent variables in multivariate regression analysis. The results of the simulation study showed that the model constructed by taking tangent coordinates as dependent variables is more appropriate than the model constructed by taking principal component scores of tangent coordinates as dependent variables, for all sample sizes.Publication Comparison of quantitative ultrasonography with dual energy absorptiometry and investigation of the correlation between quantitative ultrasonography parameters(Springer, 2004-04-01) Altan, Lale; Bingöl, Ü; Kumaş, F. F; Ercan, İlker; Yurtkuran, Merih; ALTAN İNCEOĞLU, LALE; Bingöl, Ü; Kumaş, F. F; ERCAN, İLKER; Yurtkuran, Merih; Uludağ Üniversitesi/Tıp Fakültesi/Atatürk Rehabilitasyon Merkezi; Uludağ Üniversitesi/Tıp Fakültesi//Biyostat Bölümü; AAH-1652-2021; EMT-7521-2022; FJP-3640-2022; EUN-5017-2022; EGT-2006-2022Publication Evaluation of outlier detection method performance in symmetric multivariate distributions(Taylor & Francis, 2020-02-01) Uzabacı, Ender; Ercan, İlker; Alpu, Özlem; UZABACI, ENDER; ERCAN, İLKER; Bursa Uludağ Üniversitesi/Veteriner Fakültesi/Biyoistatistik Anabilim Dalı.; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; 0000-0002-9634-0055; 0000-0002-2382-290X; JPL-5273-2023; ABF-2367-2020Determining outliers is more complicated in multivariate data sets than it is in univariate cases. The aim of this study is to evaluate the blocked adaptive computationally efficient outlier nominators (BACON) algorithm, the fast minimum covariance determinant (FAST-MCD) method, and the robust Mahalanobis distance (RM) method in multivariate data sets. For this purpose, outlier detection methods were compared for multivariate normal, Laplace, and Cauchy distributions with different sample sizes and numbers of variables. False-negative and false-positive ratios were used to evaluate the methods' performance. The results of this work indicate that the performance of these methods varies according to the distribution type.Publication Seasonal influenza vaccine awareness and factors affecting vaccination in Turkish society(Professional Medical Publications, 2022-03-01) Can, Fatma Ezgi; Yakar, Burkay; Göktaş, Olgun; ERCAN, İLKER; Akalin, Emin Halis; AKALIN, EMİN HALİS; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Tıbbi Mikrobiyoloji Anabilim Dalı.; Bursa Uludağ Üniversitesi/Aile Sağlığı Merkezi.; 0000-0002-2382-290X; 0000-0001-7530-1279; AAU-8952-2020; JSL-7718-2023Objective: Influenza vaccine reduces the burden of seasonal influenza and related complications. Potential vaccination barriers need to be identified to raise awareness and increase acceptance. We aimed to investigate the rates of seasonal influenza vaccination and the knowledge, opinions, and behaviours prevalent in Turkish society. Methods: The study among seven regions in Turkey was conducted from October-November 2018 in 28 family health centres, using a cross-sectional, descriptive design. The knowledge, opinions, and behaviours of participants regarding the influenza vaccine were obtained by family physicians through face-to-face interviews with participants. Results: A total of 3,492 people aged 10-97 years age range (median: 50 years) were included in the study. Over half of the participants (59.9%, n = 2093) were female. It was found that the percentage of participants who never received the influenza vaccine was 78.4%; only 13.4% were occasionally vaccinated, and 8.1% received regular annual vaccination. Influenza vaccination rates were higher in married people (p < 0.001), women (p = 0.005), patients with chronic lung and cardiovascular disease (p < 0.001), those over 65 years /nursing home residents (p < 0.001). Awareness of the vaccine's benefit was higher in the group at high risk of influenza (p < 0.001). Conclusion: The rate of regular vaccination against influenza every year was insufficient, at 8.1%. Individuals' insensitivity, insufficient knowledge, and attitudes toward influenza vaccination is a serious health problem for Turkish society. Barriers to influenza vaccination can be reduced by good communication between family physicians and their patients.Publication The risk of developing gestational diabetes mellitus in maternal subclinical hypothyroidism: A systematic review and meta-analysis(Springer Heidelberg, 2023-07-12) Dinçgez, Burcu; Ertürk, Nergis Kender; ERCAN, İLKER; Şahin, İbrahim; Bursa Uludağ Üniversitesi/Tıp Fakültesi/Biyoistatistik Anabilim Dalı.; 0000-0002-2382-290X; 0000-0002-2902-9670; AAH-5248-2020; GRY-0743-2022PurposeThe purpose of this study was to determine the association between maternal subclinical hypothyroidism (SCH) and gestational diabetes mellitus (GDM) risk.MethodsThis study is a systematic review and meta-analysis. Following PubMed, Medline, Scopus, Web of Science, and Google Scholar database search up to April 1 2021, a total of 4597 studies were identified. Studies published in English, with full text available, related to subclinical hypothyroidism in pregnancy, reporting or mentioning the incidence of GDM were included in the analysis. Following exclusion of studies, a total of 16 clinical trial were analyzed. For the risk of GDM, odds ratios (ORs) were calculated. Subgroup analyzes were performed according to gestational age and thyroid antibodies.ResultsPregnant women with SCH were at increased risk of GDM compared to women with euthyroidism, overall (OR = 1.339, 95% CI 1.041-1.724; p = 0.023). Additionally, SCH without thyroid antibodies has no significant effect on GDM risk (OR = 1.173, 95% CI 0.88-1.56; p = 0.277) and pregnant women with SCH in the first trimester were not found to be at increased risk of GDM compared to women with euthyroidism regardless of thyroid antibodies (OR = 1.088, 95%CI 0.816-1.451; p = 0.564).ConclusionsMaternal SCH in pregnancy is related to an increased risk of GDM.