Implementing the six sigma model on the treatment of congenital hypothyroidism: An analytical hierarchy process

Congenital hypothyroidism is a disease able to cause severe mental retardation and developmental delays. However, timely diagnosis and treatment of infants with this disease could prevent relevant complications. This study aims to investigate the effects of the implementation of the Six Sigma model on reducing the treatment initiation time in infants with congenital hypothyroidism in the population chosen from Samen Health Center in Mashhad. In this quasi-experimental study, the referral process of infants for congenital hypothyroidism screening and treatment was evaluated for the time period starting from March 20, 2017, to March 19, 2018, using the standard five-phase quality strategy, description, measurement, analysis, improvement and control phase (DMAIC), based on Six Sigma. Data were collected using the sampling form of the national screening program for congenital hypothyroidism. To analyze the data, software including Expert Choice V11, Microsoft Excel 2013, and SPSS 18, were utilized. In addition, a p-value less than 0.05 was considered statistically significant. The number of infants who entered the intervention process was 4,574, of whom 51.3% (2346 infants) were boys. The mean time to start treatment before the implementation of the model was 21.72±7.72 days, which decreased to 17.41±6.47 days after the implementation of the model (p≤ 0.05). Besides, 81.8% of the patients received treatment during infancy before the intervention, which increased to 94.1% after it. After the implementation of the Six Sigma model, the Sigma level of treatment initiation improved from 2.41 to 3.06. Six Sigma could be used as an intervention tool for improving indices of health intervention processes.