Covariates on Vision Problems and their Relationship of Rajshahi Medical College Hospital (RMCH)

Vision is very important for all living being and the sharpness of vision may be affected due to various causes like scarcity of the proper vitamins, minerals, balanced food, age and some other related covariates. The objectives of the research was to identify the influencing covariates among the 21 assigned variables of 72 patients who were suffering from various eye related problems following authors’ survey data using the purposive sampling technique. A throughout investigation and constructive analysis of the influential covariates have performed and the results are enlisted in result discussion section accordingly. As addition, history of vision problem and family history of diabetics, pathological examination, duration of diabetics and regularity in visiting doctors may have causal effect on vision problems we have given priorities on them. According to the pathological examination records only 4% patients depend on the HbA1c test, 22% on urine test and 74% on RBS test to know the diabetic status of the study area. Hypertension is one more risk factor having negative influences on the vision problem. This study shows about 39% of the patients have hypertension and rest 61% of the patients do not have hypertension. About 54% of the patients feeling that they are facing vision problem due to aged cause and rest 45% of the patients are feeling that they are facing vision problem due to diabetics. It is evident from the ophthalmic examination results that about 18% of the patients have normal vision and somewhat any deviation from normal vision have found for the rest 82% patients. The association between different covariates have been analysed following the Pearson’s Chi-Square test statistic. The asymptotic significant relation of vision has been unearthed with controlling method of diabetics and duration of hypertension will help to the concerning agencies for policy implication in the consigned area.


Introduction
Vision is very important not only for a person but also for every living being. The clarity or sharpness of vision is named as the visual acuity and it is the amiability of the eye to see and distinguish fine details. The visual problems have been seen in all aged peoples especially in the peoples of poor countries due to the deficiency of proper food and nutrition. Because the people of these countries have to face some sort of scarcity of the proper vitamins and minerals even balanced food. As a result they may suffer from such kind of vision problems. Impairment in acuity is related with difficulties in physical function of the patients [1][2][3]. An estimate by the WHO suggested that 161 million person's world-wide have visual impairment including 37 million blind and 124 million with visual impairment less severe than blindness. But total number of persons with visual impairment of the world including uncorrected refractive error was estimated as 259 million 61% higher than commonly quoted WHO estimate. The number of persons in the world with visual impairment due to uncorrected refractive error could range from 82-117 million [4]. Based on WHO blindness in Singapore is 0.5%, Malaysia is 0.3%, Taiwan is 0.6%, Bangladesh is 1.5%, Indonesia is 2.2% and India is 4.3%. Besides these the emotional distress and low socialization [5,6] are considered as the part of quality of life. As such vision may depend on so many factors, we consider that factors as covariates. A good numbers of studies have been found in the  [7] investigated eye movement of Grade 6 children with reading disabilities by three comprehension therapies. They noticed comprehension therapy likewise produced improvement both in eye movement efficiency and in reading comprehension following the notion of a cognitive link among visual attention, oculomotor readiness, and reading comprehension. Maples [8] studied two interrelated factors race and socio-economic status on classroom performance influencing the visual skills. This study identified that inefficient visual skills impact the students' learning by a total of 2,659 examinations on 540 children were administered over three consecutive school years. Socioeconomic, racial and standardized academic performance data (Iowa Test of Basic Skills-ITBS) have been used following the furnished of such data by the families and the school system. Lamoreux et al. [9] accomplished a study on basis of the Singapore Malay eye population to determine the prevalence and impact of visual impairment and major eye diseases in urban Asian populations. The authors identified the association between visual impairment and the main causes of vision loss, and falls. David et al. [10] worked on some common causes of vision problem and they reviewed the four most common causes of vision impairment in the elderly population as agerelated macular degeneration, glaucoma, cataract and Diabetic Retinopathy (DR). A cross-sectional study was conducted by Marzieh [11] using the data of 40-80 years adults aged residing in Yazd district for the period of 2010-2011. They determined the prevalence and causes of blindness and visual impairment in their study. Resnikoff et al. [12] were estimated the prevalence of visual impairment caused by uncorrected refractive errors in 2004 on both regional and global stages for the people of aged 5 and over using contemporary published and unpublished surveys. They showed that based on the prevalence of visual acuity of less than 6/18 in the better eye with the currently available refractive correction that could be improved to equal to or better than 6/18 by refraction or pinhole. According to the National Eye Institute Visual Function Questionnaire (NEI-VFQ) decreases in scores is associated with vision loss due to the eye diseases like glaucoma, DR and cataract etc. [13,14]. Visual problems may happen due to the learning causes also for the young aged population [15]. Together with these some high risk factors can be considered as i) Obesity more than 120% desirable body weight or body mass index more than 25 kg/m 2 , member of higher risk population (African, American, Hispanic, native American) and ii) Hypertensive people having blood pressure more than 140/90 mmHg.
Although in the aforesaid studies the researchers tried to investigate the vision problems in different practitioners viewpoints like ocular examination a question may arise what could be the allied variables may have joint or individual impacts on the vision oriented diseases have regarded as covariates in this research. However, the independent contributions of such covariates beyond vision problems have not been well characterized. As such inclusion of 21 more underlying variables could help to discriminate the covariates and identify the potential relationships among them according to the objectives of the research.

The covariates and risk factors
The covariates are the supporting variables that may influence the form of visualization positively or negatively. In this research we tried to identify the impact of possible covariates like Age, Sex, Marital status, Residence status, Religion, Height, Weight, Occupation, Income, Causes of vision problem, Diabetics status, Duration of diabetics, Treatment method of diabetics, Diabetic history of family members and Hypertension, Duration Diabetics and Hypertension, Regularity of visited by doctors on vision status and Taking any operation. Some socio-economic covariates have considered herewith.

Research Objectives
In this research we are very much concern to examine the related factors for vision problem. A set of related possible factors/ variables have been listed to identify the covariates of vision problems. The objectives of this research are: • To know the overall situation on vision problem for the selected area • To identify the potential factors/covariates • To measure the contribution of such covariates on vision problems.

Data collection Methods and Processing
Data collection is a mandatory part of conduction a research and proper method of collecting data may give the appropriate result of any research. The data in this research have collected from the Department of Ophthalmology (Both from indoor and outdoor) in Rajshahi Medical College Hospital (RMCH) for the period of 2nd September 2017 to 30 November 2017. As a nonprobability sampling, the Purposive Sampling has used following a structured questionnaire and interview method. MS-Excel and SPSS for windows version 20 have used to process the data.

Results
As described in the objectives, the authors were intended to measure the covariates influencing the vision oriented problems and to find their relationship with the help of 21 variables on basis of authors' survey data. The vision problem of diabetic family members of the patients has been investigated and it is found that about 25% of the diabetic family members have vision problem, 29% of the diabetic family members have not vision problem, the information of having vision problem or not of 46% diabetic family members is not known.
is the df and f ij =Observed Frequency and E ij =Expected Frequency.
The results using equation (1) are enlisted in Table 2

Conclusion
In the current study we aimed to examine whether the influences of the covariates from the assigned variables has significant effect on the vision problems on basis of the authors' survey data. A throughout investigation and constructive analysis have been performed and that are comprised in the results section. The asymptotic insignificant association of vision status to addiction category, Educational Status and Family Members have confirmed by the test. Similarly no association between Vision problem with detection methods of diabetics and type of physician visited are identified in this research. But the significant relation of association for the covariate vision problem with Age and regularities in visiting doctors have been discovered in this research. Therefore, it is reassuring that the covariates, Age and and regularities of visited by Doctors has significant impact to incongruity the vision problems of the patients could be the concern of the current research.

Limitations of the study
The establishment of more comprehensive models to ensure the aforesaid results for the eye specialist regardless of the selected covariates could eradicate one of the limitations of such study.
To follow the research design in medical data is also one more limitation.