The study attempts to develop an outpatient service quality scale by investigating the key dimensions which assess parental satisfaction and provides a recommendation on an improved health service delivery system. The survey was conducted in an Ear-Nose-Throat outpatient clinic of a Greek public pediatric hospital. A total of 127 parents in outpatient waiting areas were chosen; 74.8% of the sampled parents were under 40, and 78% were mothers. A factor analysis was performed; while a Fischer's exact test and multinomial logistic regression analysis was conducted. All Cronbach's alpha exceeded 0.70 and all factor loadings exceeded 0.50. Twenty-three items were retained through the scale development process and seven factors were formed that appear to be statistically valid and clinically meaningful: access and convenience, doctor's attention, customization, reliability, assurance, satisfaction and loyalty. Findings were discussed in relation to parents' overall satisfaction and intention of reusing and recommending outpatient clinic. Satisfaction was found to be positively affected by access and convenience and doctors' attention. Staff attitude and the telephone procedure of scheduling the child's examination found positively correlated to the likelihood of recommending services to friends and relatives. Time and communication in the waiting room influenced parents' satisfaction. Overall, results reveal the measures that need to be taken in order to improve outpatient service quality. (Contains 8 tables and 1 figure.)