Background and Objectives: Many countries still face difficulties of unequal access to health services and resource limitations. Even for high priority areas like special needs children, basic services’ coverage remains low in many countries including Malaysia. This study was conducted to determine the prevalence of missed clinic appointments by income group and their sociodemographic characteristics amongst children attending Child Development Centre at the National University of Malaysia Medical Centre. Methods: An explanatory sequential mixed method study was performed amongst caregivers of children with developmental disabilities aged up to 17 years. Results: Analysis showed 62 of 197 (31.5%) caregivers had missed clinic appointments, mostly attributed to forgetfulness. Bivariate analysis showed significant differences in missed appointment rates by caregiver gender and follow-up duration. Logistic regression model demonstrated that combined with male caregiver as an independent variable, follow-up duration of more than 6 years increased missed appointment’s risk by 2.67 times. Bottom 40% of Malaysian household income (B40) group had missed appointments of 36.8%; not statistically significant different with other income groups, denoting equitable access to our services consistent with other studies on equitable health service access in Malaysia. Sub-analysis demonstrated statistically significant differences by ethnicity and educational level. Non-Malays and those with lower educational level in B40 group demonstrated the highest proportion of missed appointments. Distance was not a risk factor amongst income groups and amongst B40 group, 85.7% who missed appointments lived less than 40KM from the centre. Caregivers’ perceived barriers were transportation, caregiver, child and healthcare services issues. Conclusions: While this study did not identify unequal access for the lower income group, supporting factors for accessibility were deemed important by caregivers and future plans should take cognizance of these findings to improve appointment adherence, equity and accessibility to services for special needs children.