Home | About us | Editorial board | Search | Ahead of print | Current issue | Archives | Submit article | Instructions | Subscribe | Contacts | Advertise | Login 
Search Article 
Advanced search 
  Users Online: 6466 Home Print this page Email this page Small font sizeDefault font sizeIncrease font size  

Table of Contents
Year : 2013  |  Volume : 17  |  Issue : 4  |  Page : 653-658

Community based diabetes risk assessment in Ogun state, Nigeria (World Diabetes Foundation project 08-321)

1 Department of Medicine, Osun State University, Osogbo, Nigeria
2 Department of Medicine, Olabisi Onabanjo University, Ago-Iwoye, Nigeria
3 Department of Medicine, Ekiti State University Teaching Hospital, Ado-Ekiti, Nigeria
4 Department of Medicine, University College Hospital, Ibadan, Nigeria
5 Federal Medical Centre, Idi Aba, Abeokuta, Nigeria
6 Department of Medicine, Obafemi Awolowo University Teaching Hospital, Ile-Ife, Nigeria
7 Department of Health Services, University of Agriculture Abeokuta, Ogun State, Nigeria

Date of Web Publication20-Jun-2013

Correspondence Address:
Olutayo C Alebiosu
Department of Medicine, Osun State, University, Osogbo, Osun
Login to access the Email id

Source of Support: World Diabetes Foundation, Conflict of Interest: Fund was provided by the World Diabetes Foundation to run this project (WDF 08-321).

DOI: 10.4103/2230-8210.113756

Rights and Permissions

Objective: The study assessed the risk of developing type 2 diabetes Mellitus in Ogun State, Nigeria. Materials and Methods: Finnish Medical Association diabetes risk score was administered across 25 communities facilitated by non-communicable disease clinics established under a World Diabetes Foundation project. Subjects in the high risk group had blood glucose estimated. Results: 58,567 respondents included 34,990 (59.6%) females and 23,667 (40.3%) males. Majority (61.2%) were between 25 years and 54 years. Considering waist circumference, 34,990 (38.1%) females and 23,667 (5.3%) males had values above 88 cm and 102 cm respectively. Overall, 11,266 (19.2%) were obese and 28.9% overweight using body mass index (BMI). More females had elevated BMI than males. Mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) of all subjects were 129.54 mm Hg ± 23.5 mm Hg and 76.21 mm Hg ± 15.5 mm Hg respectively. Prevalence of hypertension (Joint National Committee VII classification) was 27.7%. More subjects had normal DBP than SBP (68.2% vs. 42.5% P < 0.05). Mean fasting blood glucose (FBG) of all subjects was 5.5 mmol/L ± 0.67 mmol/L. Using a casual blood glucose >11.1 mmol/L and/or FBG >7 mmol/L, the total yield of subjects adjudged as having diabetes was 2,956 (5.05%). Mean total risk score was 5.60 ± 3.90; this was significantly higher in females (6.34 ± 4.16 vs. 4.24 ± 3.71, P < 0.05). A total of 2,956 (5.05%) had high risk of developing DM within 10 years. Conclusion: The risk of developing DM is high in the community studied with females having a higher risk score. There is urgent need to implement diabetes prevention strategies.

Keywords: Community, diabetes risk, Nigeria, survey

How to cite this article:
Alebiosu OC, Familoni OB, Ogunsemi OO, Raimi T H, Balogun WO, Odusan O, Oguntona SA, Olunuga T, Kolawole BA, Ikem RT, Adeleye JO, Adesina OF, Adewuyi PA. Community based diabetes risk assessment in Ogun state, Nigeria (World Diabetes Foundation project 08-321). Indian J Endocr Metab 2013;17:653-8

How to cite this URL:
Alebiosu OC, Familoni OB, Ogunsemi OO, Raimi T H, Balogun WO, Odusan O, Oguntona SA, Olunuga T, Kolawole BA, Ikem RT, Adeleye JO, Adesina OF, Adewuyi PA. Community based diabetes risk assessment in Ogun state, Nigeria (World Diabetes Foundation project 08-321). Indian J Endocr Metab [serial online] 2013 [cited 2020 Oct 26];17:653-8. Available from: https://www.ijem.in/text.asp?2013/17/4/653/113756

   Introduction Top

Over time, diabetes mellitus (DM) has emerged as a global healthcare problem that has reached epidemic proportions. [1] It is a major risk factor for cardiovascular disease, with a 2-4 fold increase risk compared with persons who do not have diabetes. [2] DM is the leading cause of blindness, non-traumatic amputations, and end-stage renal disease. [3],[4],[5]

The health systems in many countries are not equipped to meet the rising challenges of diabetes care and non-communicable diseases (NCD). Type 2 DM accounts for approximately 90-95% of all cases of diabetes worldwide and the current diabetes epidemic is attributable to rising cases of type 2 diabetes. [6] A complex interplay of genetic susceptibility and environmental/lifestyle factors such as overweight/obesity, physical inactivity, and a high-fat/low-fiber diet is believed to be driving the global explosion in type 2 DM. [7]

In some of the poorest regions in the world such as Africa, where infectious diseases have traditionally been the focus of healthcare systems, diabetes cases are expected to increase by 90% by 2030. [8] At least 78% of people in Africa are undiagnosed and do not know they are living with diabetes. [8] Recent figures released by the International Diabetes Federation (IDF) indicate that the number of people living with diabetes is expected to rise from 366 million in 2011 to 552 million by 2030, if no urgent action is taken. [8] This equates to approximately three new cases every 10 s or almost 10 million per year. The IDF recently estimated that as many as 183 million people are un-aware that they have diabetes. Presently, more than three-quarters of the estimated 179 million people with diabetes are in the 40-59 age range. [8]

In sub-Saharan Africa, the proportion of people with undiagnosed diabetes can reach up to 90% in some countries compared to about one-third undiagnosed people in high-income countries. [8]

Some of Africa's most populous countries also have the highest number of people with diabetes, with Nigeria having the largest number of people (3.0 million), followed by South Africa (1.9 million), Ethiopia (1.4 million), and Kenya (769,000). [8] The crude prevalence of DM in a national survey conducted in 1992 in males and females below the age of 45 years was 1.6% and 1.9%, respectively; with a 3-fold increase after the age of 45 years to 5.4% and 5.6% in males and females, respectively. [9] Urban communities had a higher overall prevalence of diabetes (3.3%) when compared with rural communities (2.6%). [9] The recent IDF data (2011) estimated the prevalence of diabetes in Nigeria to be 4.04%, compared to Reunion (highest in Africa [16.78%]), Benin (1.71%), Ghana (4.09%), Niger (4.36%), Cameroun (5.18%), and South Africa (6.46%). [8]

Globally, the diabetes pandemic is driven by an increase in the adult population, increased longevity, and changes in behavior associated with rapidly increasing urbanization and development. The key changes in behavior include reduced physical activity, a shift to highly energy dense calorie diets, with associated increase in obesity.

Knowledge of diabetes care by healthcare workers in many Nigerian health establishments is generally poor. This has resulted in inadequate care for many persons with diabetes in Nigeria. Earlier studies showed that a large number of healthcare workers in Southwest Nigeria, in the absence of a Nigerian National guideline, were unfamiliar with the current practice guidelines of the American Diabetes Association for the management of diabetes. [10],[11],[12]

The main objective of the study was to assess the risk of developing type 2 diabetes over 10 years in communities across Ogun State, Nigeria as part of the World Diabetes Foundation (WDF) sponsored Project 08-321 (strategies for improving diabetes care in Nigeria [SIDCAIN]).

   Materials and Methods Top

The study was part of the WDF sponsored WDF 08-321 Project in Ogun State, Nigeria. This is a diabetes education program aimed at preventing and improving overall diabetes care in Nigeria and thus preventing/delaying the onset of complications.

Ethical clearance was obtained from the Health Research and Ethical Committee of the Olabisi Onabanjo University Teaching Hospital, Sagamu, and the procedures followed were in accordance with the ethical standards of this institutional committee on human experimentation and with the Helsinki Declaration of 1975, as revised in 2000. Written approval for the project was also obtained from the Ogun State Health authorities.

Study design

This was an observational research study. The study involved all the 20 local government areas of Ogun State. One healthcare institution was randomly selected from each local government area of the State. Healthcare workers including two medical officers, three nurses, and a laboratory scientist were randomly selected from health institutions from each of these 20 local government areas, and given an intensive training over a 3-week period. Six resource staff served as trainers for the program. Relevant additional and locally available and willing resource personnel were sourced when required, from the nearest tertiary health institutions. Baseline knowledge of diabetes and hypertension care among healthcare workers at the primary and secondary healthcare levels within the selected local government areas was assessed through a structured questionnaire. The healthcare workers within the selected local government areas in the state were re-trained using the IDF training module for Africa. [13] Each training program was completed within 3 weeks. The training program was stratified into two: All willing healthcare workers were accommodated within the 1 st week of the training program. The remaining 2 weeks were concentrated on the participating and willing middle cadre healthcare providers. Pre- and Post-training tests were administered.

Selection and description of participants

Diabetes risk assessment was carried out with the use of the Finnish Medical Association [Table 1]. [14] The questionnaire consists of eight items, some of which are questions while others are patient's biodata. The total risk score (TRS) for each study participant was the summation of all the scores.
Table 1: Type 2 diabetes risk assessment questionnaire

Click here to view

NCD clinics were established and incorporated into the existing infrastructure of the selected health institutions in all the 20 local governments. The selected trained healthcare workers formed the core staff of the established NCDs clinics. The NCD clinics were provided with NCD registers for documenting patients' biodata, key clinical and laboratory data, and diabetes care records. Each NCD Clinic was also provided with a "NCD Clinic Pack" that includes a sphygmomanometer, stadiometer, two glucometers, test strips, and a stethoscope. The NCD clinics were operated on a revolving account basis so as to ensure regular supply of test strips.

The NCD clinics were involved in diagnosis, assessment and treatment of persons with diabetes, health education, maintenance and regular review of metabolic control, continuing health education, and appropriate timing of referral to secondary and tertiary healthcare levels when indicated. Continuous (in-service) diabetes education was organized for the healthcare givers in the established clinics. Recruited program facilitators reviewed the activities of the NCD Clinics at the end of every month including the NCD register using a protocol and data collection form.


Data so obtained were entered into a computerized database located at the Program Coordinators Office. Data were analyzed using the Statistical Package for Social Sciences (SPSS) for Windows, version 11 software (SPSS Inc., Chicago, IL). A P < 0.05 was considered statistically significant. The data were expressed as mean ± SD.

In addition to providing regular diabetes care, the NCD clinics facilitated events to increase the awareness of diabetes in the surrounding communities. The risk of developing type 2 diabetes within 10 years was stratified into: Low (<7), slightly elevated (7-11), moderately elevated (12-14), high (15-20), and very high (>20).

Inclusion and exclusion criteria

The inclusion criterion is any consenting non-diabetic adults attending the free screening camps organized by any of the established NCD clinics. Subjects with normal blood pressure but on anti-hypertensives were included. The exclusion criterion is an established diagnosis of DM.

Blood pressure was measured by trained research assistants in accordance with standard procedure. Blood glucose was determined using glucometers that were previously calibrated with laboratory measurements. Only subjects in the high-risk group had their blood glucose estimated with a glucometer. Diabetes was diagnosed using a Random Blood Glucose ≥11.1 mmol/L and/or Fasting Blood Glucose ≥7 mmol/L.

   Results Top

Demographic data

Out of a total of 58,657 subjects screened by the NCD clinics, no known diabetic patients were included. The screening tool excludes known diabetics. The number comprises of 34,990 (59.6%) females. [Table 2] shows the demographic data of all the study subjects. The mean age of all subjects was 40.69 years ±16.27 years.
Table 2: Demographic, anthropometric and clinical data of the study population (n=58,657)

Click here to view

Blood glucose distribution

The mean fasting blood glucose (FBG) was 5.5 mmol/L ± 0.67 mmol/L. The total yield of subjects adjudged as having diabetes was 2,956 (5.05%).

Blood pressure distribution

Mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) of all the subjects were 129.54 mmHg ± 23.5 mmHg and 76.21 mmHg ± 15.5 mmHg, respectively [Table 3]. There was no significant difference in the SBP and DBP of the male and female subjects at 130.28 mmHg ± 22.04 mmHg versus 129.11 mmHg ± 25.24 mmHg and 76.43 mmHg ± 15.6 mmHg versus 76.05 mmHg ± 15.86 mmHg, respectively (P > 0.05). The prevalence of hypertension using the JNC VII classification in the subjects was 27.7%.
Table 3: Blood pressure frequency distribution of all subjects (%)

Click here to view

Body mass index

A total of 13,091 (22.3%) females had waist circumference (WC) greater than 88 cm, whereas 1,161 (2.0%) males had WC greater than 102 cm [Table 4]. Mean body mass index (BMI) for all subjects was 25.18 kg/m 2 ± 5.62 kg/m 2 . The mean male BMI of 25.3 ± 4.35 was similar to that of females (26.12 ± 6.22, P > 0.05). About half (54.2%) of females had BMI >24.9 Kg/m 2 compared with 47.1% of males, P > 0.05; however, significantly more females were obese (BMI >30) (24.8% vs. 10.8%, P < 0.05).
Table 4: Gender distribution of body mass index (%)

Click here to view

Total risk score

Using the Finnish diabetes risk scoring, less than one-tenth (8.6%) of all the subjects were in the high and very high-risk groups, majority were in the low-risk group (<7). [Table 5] and [Table 6] show the pattern of risk stratification of the study population.
Table 5: Risk of developing type 2 diabetes amongst study subjects

Click here to view
Table 6: Demographic data of high risk subjects versus low risk subjects

Click here to view

The mean TRS was 5.68 ± 3.90. The TRS was significantly higher in the female subjects than males (6.34 ± 4.16 vs. 4.24 ± 3.71, P < 0.05). In all the subjects, the TRS correlated positively with FBG (r = 0.324, P = 0.000). This holds true when male and female subjects were separately considered.

   Discussion Top

The purpose of community-based screening for NCD is to differentiate asymptomatic individuals at high risk from individuals at low risk. [14],[15] Ideally, screening tests should be rapid, simple, and safe. [14],[15] When returned positive, the screening test only means that the person is more likely to have the disease than a person with a negative screening test. Screening for diabetes and hypertension can identify patients at an early stage of the diseases, and identify those that will derive benefit from prevention and early treatment methods.

The Finnish diabetes risk score is a simple, fast, inexpensive, non-invasive, and reliable tool to identify individuals at high risk for type 2 diabetes. [14],[15] The Finnish diabetes risk score has been previously validated among Nigerians. [16]

Globally, a changing disease pattern tilting toward NCD preponderance has been documented in epidemiological predictions and observational data. [8] Till date, this is perhaps one of the largest community-based studies on NCD in Nigeria. This is the strength of this study. The National Population Study on NCDs conducted by the Federal Ministry of Health in Nigeria which covered all the states of the Federation remains the only nation-wide data available till date. [8]

Our data showed that only 1/5 (21%) of the subjects were older than 55 years. Hypertension and type 2 diabetes which tend to increase with age might have been under-represented in this cohort which comprised essentially young-and middle-aged subjects.

The mean FBG was 5.5 mmol/L ± 0.67 mmol/L. Using a casual blood glucose >11.1 mmol/L and/or FBG >7 mmol/L, the total yield of subjects adjudged as having diabetes was 2,956 (5.05%).

This is higher than the National average of 2.2% (1992) but a little higher than the recent estimate for the country released by the IDF (4.04%). [8] This figure may even be on the low side because of the age range of participants. [8] The mean FBG of 5.5 mmol/L ± 0.67 mmol/L is also rather high for a community screening and should be a source of concern and a call for urgent action!

Prevalence of hypertension using the JNC VII in the study subjects was 27.7%. This is slightly higher than the National average of 20%. [9] About two-thirds of our hypertensives had stage 1 hypertension which is in consonance with the National consensus. There was no difference in the number of male and female hypertensives. More subjects had normal DBP than SBP (68.2 vs. 42.5, P < 0.05), underscoring a trend toward systolic hypertension.

The prevalence of central obesity is low among the male subjects as compared with the female where more than one-third had abnormal WC. The difference between the sexes was significant (38.1% female >88 cm vs. 5.3% male >102 cm, P < 0.05).

Pearson's correlation showed that exercising did correlate with abdominal obesity. In all the subjects, the TRS correlated positively with FBG (r = 0.324, P = 0.000). This holds true when male and female subjects were separately considered. The TRS was significantly higher in female subjects than males (6.34 ± 4.16 vs. 4.24 ± 3.71, P < 0.05).

It was observed that males and the older age group were more in the high-risk population. Students were more in the low-risk group, whereas traders were more in the high-risk group. This may be because of the younger age of students as well as likely increased activity, whereas trading as an occupation predisposes to sedentary lifestyle and subsequently overweight/obesity. However, student as a profession would have age as a confounding factor. It is interesting that the consumption of vegetables did not significantly differ between the low- and the high-risk groups.

One limitation of our study is the use of glucometer to determine blood glucose in the subjects. Although a calibrated equipment is allowed in field study, there could have been an over- or under-representation of diabetes prevalence. This is because a number of factors can affect the accuracy of glucose meter results, including operator technique, environmental exposure, and patient physiological and medication effects. [17]

The high risk of developing type 2 diabetes among indigenes of Ogun State, Nigeria corroborates the current global diabetes epidemic. The higher risk scores observed in females reflect the female preponderance of overweight and obesity in our communities.

   Conclusion Top

The risk of developing type 2 diabetes within 10 years is unarguably high among the study participants. There is thus an urgent need to implement diabetes prevention strategies that include health education policies geared toward adoption of healthy lifestyle measures that prevent or delay the onset of type 2 diabetes.

Future research directions: In view of the global projections of diabetes epidemic and the outcome findings of this study, there is a need for a national research on diabetes in Nigeria. This must be a prospective study coordinated by the Federal Ministry of Health.

   References Top

1.Alebiosu CO, Familoni O, Ogunsemi O, Raimi TH, Balogun W, Odusan O et. al. Strategies for improving diabetes care in nigeria (SIDCAIN) Research Group. Methods and study protocol. nigerian endocrine practice. 2009;3:13-26.  Back to cited text no. 1
2.Wingard DL, Barrett-Connor E. Heart disease and diabetes. In: Diabetes in America. 2 nd ed. Bethesda: NIH Publication; 1995. p. 429-48.  Back to cited text no. 2
3.Aiello LP, Gardner TW, King GL, Blankenship G, Cavallerano JD, Ferris FL 3 rd , et al. Diabetic retinopathy. Diabetes Care 1998;21:143-56.  Back to cited text no. 3
4.Mayfield JA, Reiber GE, Sanders LJ, Janisse D, Pogach LM. Preventive foot care in people with diabetes. Diabetes Care 1998;21:2161-77.  Back to cited text no. 4
5.Lok CE, Oliver MJ, Rothwell DM, Hux JE. The growing volume of diabetes-related dialysis: A population based study. Nephrol Dial Transplant 2004;19:3098-103.  Back to cited text no. 5
6.King H, Aubert RE, Herman WH. Global burden of diabetes, 1995-2025: Prevalence, numerical estimates, and projections. Diabetes Care 1998;21:1414-31.  Back to cited text no. 6
7.WHO. Diabetes cases in Africa to double in next 25 years. Bull World Health Organization, ISSN 0042-9686. 2004;82:397-8.  Back to cited text no. 7
8.International diabetes foundation. Diabetes atlas. Available from: http://www.idf.org/diabetesatlas/.[Last accessed 2012, July, 2].  Back to cited text no. 8
9.Akinkugbe OO. Non-Communicable diseases in Nigeria-Final report of a national survey. Lagos: Federal ministry of health-national expert committee on NCD. Ibadan: Spectrum Books Limited (Publishers); 1997. p. 1-12.  Back to cited text no. 9
10.Alebiosu CO, Familoni O, Ogunsemi O, Raimi TH, Balogun W, Odusan O et. al. Strategies for Improving Diabetes Care in Nigeria Research Group. Knowledge of diabetes and hypertension care among health care workers in southwest Nigeria. Postgrad Med 2009;121:173-7.  Back to cited text no. 10
11.Kolawole BA, Adegbenro C, Adegoke S, Adeola OG, Akintan TB, Ojoawo IO. Effectiveness of a structured diabetes education program on some non-glycemic endpoints in Nigerians with type 2 diabetes mellitus. Int Q Community Health Educ 2008-2009;29:381-8.  Back to cited text no. 11
12.Alebiosu CO, Obi EO, Ogunsemi O, TH. Assessing the degree of success for American Diabetes Association clinical goals among diabetic subjects in a teaching hospital setting in Nigeria. Nigeria Endocrine Practice. 2008;2:79-85.  Back to cited text no. 12
13.International Diabetes Federation. Diabetes education training module. Available from: http://www.idf.org/diabetes-education-modules. [Last accessed 2012, August, 27].  Back to cited text no. 13
14.Lindström J, Tuomilehto J. The diabetes risk score: A practical tool to predict type 2 diabetes risk. Diabetes Care 2003;26:725-31.  Back to cited text no. 14
15.Schwarz PE, Li J, Lindstrom J, Tuomilehto J. Tools for predicting the risk of type 2 diabetes in daily practice. Horm Metab Res 2009;41:86-97.  Back to cited text no. 15
16.Busari OA, Opadijo OG, Adeyemi AO. Risk of developing diabetes amonghealthcare workers in a Nigerian tertiary hospital. Mera: Diabetes International. 2008. p. 21-2.  Back to cited text no. 16
17.Tonyushkina K, James H, Nichols. Journal of Diabetes Science and Technology 2009;3:971-80.  Back to cited text no. 17


  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]

This article has been cited by
1 Cardiopulmonary health indices and diabetes risk scores in undergraduate students of a private university in Nigeria
JolaOluwa Oluwatosin Yesufu,Olaoluwa David Oluwasile,Olufemi Idowu Oluranti,Adesoji Adesipe Fasanmade,Ayodele O. Soladoye
Beni-Suef University Journal of Basic and Applied Sciences. 2020; 9(1)
[Pubmed] | [DOI]
2 Prevalence and correlates of traditional risk factors for cardiovascular disease in a Nigerian ART-naive HIV population: a cross-sectional study
Udeme E Ekrikpo,Effiong E Akpan,John U Ekott,Aminu K Bello,Ikechi G Okpechi,Andre P Kengne
BMJ Open. 2018; 8(7): e019664
[Pubmed] | [DOI]
3 Herbal medicine use among Type 2 diabetes mellitus patients in Nigeria: understanding the magnitude and predictors of use
Ogochukwu Ukamaka Amaeze,Roseline Iberi Aderemi-Williams,Modupeola Anuoluwapo Ayo-Vaughan,Deborah Aderoju Ogundemuren,Damilola Segun Ogunmola,Emmanuel Nwanolue Anyika
International Journal of Clinical Pharmacy. 2018;
[Pubmed] | [DOI]
4 Determining type 2 diabetes risk factors for the adults: A community based study from Turkey
Gulhan Cosansu,Selda Celik,Seyda Özcan,Nermin Olgun,Nurdan Yildirim,Hulya Gulyuz Demir
Primary Care Diabetes. 2018;
[Pubmed] | [DOI]
5 Prevalence of type 2 diabetes mellitus in Southern Cross River: a cross-sectional observational survey
Akaninyene Otu,Margaret Akpan,Emmanuel Effa,Victor Umoh,Ofem Enang
International Journal of Diabetes in Developing Countries. 2018;
[Pubmed] | [DOI]
6 Diabetes Care in Nigeria
Olufemi A. Fasanmade,Samuel Dagogo-Jack
Annals of Global Health. 2015; 81(6): 821
[Pubmed] | [DOI]
7 Evaluation of Finnish Diabetes Risk Score in Screening Undiagnosed Diabetes and Prediabetes among U.S. Adults by Gender and Race: NHANES 1999-2010
Lu Zhang,Zhenzhen Zhang,Yurong Zhang,Gang Hu,Liwei Chen,Shengxu Li
PLoS ONE. 2014; 9(5): e97865
[Pubmed] | [DOI]
8 Cardiovascular risk factors in semi-urban communities in southwest Nigeria: Patterns and prevalence
Rotimi Oluyombo,Michael A. Olamoyegun,Oluwasegun Olaifa,Sandra O. Iwuala,Oluwole A. Babatunde
Journal of Epidemiology and Global Health. 2014;
[Pubmed] | [DOI]


    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

  In this article
    Materials and Me...
    Article Tables

 Article Access Statistics
    PDF Downloaded354    
    Comments [Add]    
    Cited by others 8    

Recommend this journal