Behavioural and emotional issues among primary school pupils with congenital colour vision deficiency in the Federal Territory of Kuala Lumpur, Malaysia: A case-control study

Introduction

Normal colour vision (NCV), in which, all of the three types of retinal cones are functioning well, is a vital attribute of visual perception. The importance of NCV is observed even in the early years of a person life as colour plays a vital role in teaching, which helps to improve memory and increase pupil’s interest in the learning process (Bhoopal & Arya, 2016). However, the excessive use of colours in teaching and learning at primary schools may create confusion and a less favourable learning environment to pupils with congenital colour vision deficiency (CCVD), whose absorption spectra of cone pigments are defective.

A cross-sectional study conducted by Reddy & Hassan (2006) among 1214 primary school pupils aged between seven and 12 years old in Petaling Jaya, Malaysia, showed an overall CCVD prevalence rate of 2.60% with a significant male predominance of 4.80% and 0.20% for female. This indicates that in every classroom of 40 pupils, one or two male pupils is/are expected to have CCVD. In Malaysia, school vision screenings are conducted at primary one, which is at the age of 7. However, they do not provide screening for colour vision. This may cause pupils with CCVD to be unaware of their condition. Hence, they may not be able to adapt well with their surroundings, which may lead to behavioural, emotional and social issues. This may subsequently result in a decline in overall academic performance (Espinda, 1971) as well as having a negative impact on the individual’s self-confidence (Bailey, 2013).

The main objective of this case-control study was to compare behavioural and emotional issues among primary school pupils with CCVD (as case) and age, gender and class-matched pupils with normal colour vision (NCV) (as controls) in the Federal Territory of Kuala Lumpur, Malaysia using the Malay language (Bahasa Melayu) adapted version of Child Behaviour Checklist/ages 4-18 (CBCL/ 4-18). The CBCL/ 4-18 is used to access behavioural and emotional problems (also known as behavioural syndromes). It has three broad groupings of syndromes scale: Internalising Problems, Externalising Problems and Total Problems. Internalising Problems combines the sub constructs of Withdrawn, Somatic Complaints, and Anxiety/Depression sub constructs, while Externalising problems combines the Delinquent Behaviour and Aggressive Behaviour sub constructs (Achenbach, 1991). The Total Problems combines the scores of all the sub constructs (Brown & Achenbach, 1992). The Child Behaviour Checklist/ages 4-18 (CBCL/ 4-18) has been translated and validated into 75 languages, and it is widely used for clinical diagnosis and in research (Ivanova et al., 2010). To date this questionnaire has not been used to study the behavioural and emotional problems among pupils with CCVD. The CBCL/ 4-18 has been widely used previously in various studies among children in Malaysia, and it was found that this checklist was a good screening tool for the maladjusted (Normah & Shalisah, 1999; Talib et al., 2011; Teoh, 2010). Studying the significance of this issue is important to assist in the early clinical management such as adaptive strategies and early counselling for the children with CCVD.

Methods

The study is reported in accordance with the STROBE case-control reporting guidelines (von Elm et al., 2007).

Procedure

Consent forms and information sheets were given to all pupils to obtain their parent’s consent to allow them to participate in this study. Only those with their parent’s consent were recruited. Participant’s parents were informed that all collected data would remain confidential.

Firstly, visual acuity and colour vision screening were conducted by the researcher at the selected schools from February 2018 till May 2018 to identify pupils with CCVD. Pupils who passed the inclusion criteria, underwent the visual acuity measurement which was conducted at both distant (6 metres) and near (40 cm) using the Early Treatment Diabetic Retinopathy Study (EDTRS) chart and colour vision screening using Ishihara 24-Pseudoisochromatic Plates (Kanehara Trading Co. Ltd, Tokyo, Japan) and followed by Farnsworth D-15 test (Munsell Color Company, Inc., Baltimore, MD, USA). The Ishihara 24-plates were performed by holding them under daylight at a distance of 50 cm and tilted so that each plate was at right angles to the line of vision. The time allocated to read each plate was less than 5 seconds. Those who failed to read four or more plates, were then asked to arrange 15 coloured caps on the Farnsworth D-15 test. To perform this test, pupils were instructed to arrange 15 randomly ordered coloured caps in order of hue with a reference coloured cap placed at the starting point for them to arrange the rest of the caps in an order. When the pupil had completed the test, the cap sequence is plotted and based on the number and direction of major crossovers on the plot, the type of colour vision deficiency were determined.

Then, pupils who were identified having CCVD and an equal number of age, gender and class-matched pupils with NCV were required to obtain consent of their mother to be respondents in this study. Only mothers of pupil who agreed were recruited and given the self-administered CBCL/ 4-18 questionnaire to be completed to illustrate any issues in their child’s behaviour and emotional state. Demographic data of all the pupils, which included age and type of colour vision deficiency (for pupil with CCVD), as well as their mothers’ which included age, race, education level, family income (monthly), marital status, medical and ocular history of the child, and awareness of their child’s colour vision problem were also recorded. A flow diagram of the participant recruitment procedure is as shown in Figure 1.

Figure 1. Flow diagram of participant recruitment procedure.

Results

The demographic data of mothers and their children with CCVD and NCV who agreed to be recruited as respondents in this study are shown in Table 1. The majority (86.36% of mothers of pupils with CCVD, and 72.72% of mother of pupils with NCV), were within 31 to 50 years old and mostly are married. About 45.45% of mother of pupils with CCVD and 38.64% of mother of pupils with NCV had undergraduate degrees, and most of them had a monthly family income of RM (Malaysian ringgit) 4,001-RM 6,000. Only 15.91% of mothers of pupils with CCVD stated that they were aware of their child’s condition. All aged-matched pupil in both the CCVD group and NCV group were within the age group of 8 to 11 years old (µ =9.47, σ =1.04). Among those with CCVD, 33 (75.00%) were identified as deuteranomalous trichromats and 11 (25.00%) as protanomalous trichromats. All mother of pupils with CCVD and NCV ruled out any known medical and ocular history of the child.

A normality test was conducted on each sub construct to determine the distribution of data. The Shapiro-Wilk, W, test for all eight sub constructs and combination of sub constructs, revealed a p-value <0.05 which shows that all data were not normally distributed. Descriptive statistical analysis results for the CBCL/ 4-18 questionnaire are presented based on raw score which had been converted into standard scores (T-score, µ =50 and σ =10). The conversion to T-score allows the comparison of scores obtained with normative data from other pupils of the same age range as shown in Table 2 (Achenbach, 1991). Based on the frequency analysis, the scores for all eight sub constructs and the three broad groupings of behavioural syndrome were within the normal range of both groups as shown in Figure 2.

Figure 2. Comparison of Child Behaviour Checklist (CBCL)/ 4-18 Problem Scale Profile for pupils with congenital colour vision deficiency (CCVD) and normal colour vision (NCV).

Horizontal broken lines = Borderline clinical range.

As the data were not normally distributed, non-parametric statistical analysis, Mann-Whitney U test, was chosen to compare the results for both groups. As illustrated in Table 3, significantly higher scores were observed for the CCVD group in Externalising Problems (U=697.50, p=0.02) and Total Behaviour Problems (U=647.00, p=0.01). Similarly, significantly higher scores for the CCVD group were also observed in the sub constructs Withdrawn (U=714.00, p=0.02), Thought Problems (U=438.50, p< 0.001) and Aggressive Behaviour (U=738.00, p=0.04).

Subsequently, odds ratios were calculated with 95% confidence intervals (CI) as estimates of the relative risk for high Total Behaviour Problem, Externalising Problems, Withdrawn, Thought Problems and Aggressive Behaviour scores among children with CCVD compared with the control group. When a cut-off was applied at the T-score ≥60, which indicates borderline clinical behavioural syndrome, odds for high scores on the Total Problems scale was 2.39(CI 1.0-5.7), Externalising Problems was 2.32 (CI 1.0-5.5), Withdrawn was 2.67(CI 1.1-6.5), Thought Problems 9.64 (CI 3.6-26.1) and Aggressive Behaviour was 10.26 (CI 3.4-31.0) as shown in Table 4.

Discussion

This study compares behavioural and emotional issues among primary school pupils with CCVD and NCV. The results from this study suggest that pupils with CCVD presented more behavioural and emotional problems as compared to NCV pupils. It is found that CCVD pupils might be at a higher risk of developing social and attention problems. Pupils with CCVD having high scores for sub construct of Withdrawn tend to present with behaviours such as preference to be alone, shy, staring blankly and show signs of sadness. Socially withdrawn pupil aged above 7 years, often encounter problems in social interactions with peers and social skills (Fink et al., 2015). Moreover, with increasing age social withdrawal becomes accompanied by feelings of loneliness and depression (Matthews et al., 2015). This may contribute to acting-out behavior in form of social aggression that are associated with behaviours such as arguing, screaming, showing off, attention-seeking, bragging, teasing, being demanding, threatening behaviour and being temperamental. Furthermore, pupils’ class participation and social skills is an important contributor to their academic competence (Rabiner et al., 2016). Additionally, pupils with CCVD having a combination of social withdrawal, aggressive behavior, along with thought problems with characteristics of obsessing on certain thoughts, finding it difficult to concentrate, staring blanking and having strange ideas or behaviours, can diminish the ability to learn, which affects academic performance (Rhoades et al., 2011).

Our finding revealed that pupils with CCVD are experiencing more internalising problems. There is a possibility that in general, people are better at recognising pupil’s externalising problems, such as aggression, internalising problems such as depression and social withdrawal. This is because externalising problems may be more likely to induce a sense of worry in the people surrounding them, while the internalising problems faced by these pupils may be overlooked by their parents and teachers who are unaware of the pupil’s colour vision impairment. This problem can be overcome by an early colour vision screening. For screening, the Ishihara test is widely used as it is quick and easy to administer, inexpensive, and has a high validity (Birch, 1997). Though, in a recent published review article on ‘Is screening for congenital colour vision deficiency in school students worthwhile?’, Ramachandran & colleagues (2014) stated that there’s minimal evidence to support the screening for CCVD in school. However, this article has received disagreement from other researchers. Based on personal experience with congenital colour vision defects, Cole (2015) agree to disagree with the conclusion made by the writer. He believes that pupils with CCVD do need to know about their condition before the end of their schooling. This is also supported by Long & colleagues (2015) as they believe that delaying the diagnosis and awareness of CCVD may create significant emotional and psychological impact. Based on their clinical perspective of working with young adults having CCVD, they see many of them who comes for a comprehensive colour vision examination for job or tertiary education recruitment, often gets shocked which accompanied with grief, disbelief and anger upon discovering their condition. Thus, an early colour vision screening is school would be the best option. This will enable useful early counselling and adaptive strategies to be implemented especially in classrooms as early as possible.

Classroom behaviour is very important in primary school life and pupils who display problematic behaviours also tend to have deficits in social and emotional skills (Wagner & Ruch, 2015). Besides that, behavioural problems present in early childhood may develop into greater problems in later life (Ogundele, 2018). It is therefore important to broaden the age range of the current study in order to take into account mental health problems across the different stages of childhood development such as preschool and secondary school. Research has found generally pupils’ behavioural problems differ according to gender. Previous studies conducted among pupils from various cultures have found that male pupils are more likely to achieve higher scores on Externalising Problems as compared to Internalising Problems (Achenbach et al., 1990; Achenbach et al., 1990).

A limitation of this study was having no data from female pupils with CCVD due to the very low prevalence rate. Thus, in the present study, CBCL/ 4-18 data was only collected from age and class-matched male pupils in both case and control groups for comparison. Therefore, it is not possible to compare scores between male and female pupils. However, this study showed that male pupils with CCVD had significantly higher scores as compared to the male pupils in the control group with NCV. Further understanding of the behavioural problems among female pupils with CCVD is recommended for future studies. Our findings should also be viewed in the context of some methodological limitations. Because this study was conducted in national primary schools in Malaysia, most pupils with CCVD were mainly Malay with only one Chinese and one Indian. Thus, our findings may not generalise to minorities. Future studies are to be conducted in vernacular schools.

Conclusion

In conclusion, the analysis of the CBCL/ 4-18 showed that the scores for all problem sub constructs obtained by pupils with CCVD were within the normal range. However, their scores were higher than of their peers with NCV, which suggest that the pupils with CCVD present more behavioural and emotional problems as compared to NCV pupils. These findings provide important new data on the behavioural and emotional problems of Malaysian primary school pupils with CCVD. This study emphasises the importance of additional studies to be conducted to understand this issue in depth which provides insight to assist in the clinical management of the CCVD children. Thus, early school visual screening in Malaysia should also include colour vision so that the child, their family, and school teachers are aware of their condition as early as possible to ensure the well-being of the child.

Data availability

Harvard Dataverse: Dataset 1. Demographic Data & CBCL/4-18 Scores-Behavioural and Emotional Issues among Primary School Pupils with Congenital Colour Vision Deficiency in Federal Territory of Kuala Lumpur, Malaysia. https://doi.org/10.7910/DVN/DPZHI4 (Thomas et al., 2018)

Ethics approval

Ethical approval for this study was obtained from the Research and Ethics Committee of Universiti Kebangsaan Malaysia (UKMREC Approval Number: UKM PPI/111/8/JEP-2016-326).

Consent

Written informed consent for publication of the participants details were obtained from the participants.