This study evaluates the impact of the recently developed BSSI on diabetic adults in Pakistan. A comparative analysis was conducted between BSSI, body mass index (BMI), and body surface area (BSA) to assess the performance of BSSI and identify ideal measures that can accurately predict the incidence of diabetes in Pakistani adults. The research is based on a cross-sectional dataset collected from 1,928 individuals in Pakistan over 2-years. Pregnant women were excluded from the study, and all participants aged 20 years or older, including both males and females, were included and provided required information. Quantile regression curve analyses were employed to investigate the projecting influence of baseline BSSI, BSA, and BMI on the development of Type-2 diabetes. The findings revealed that during the follow-up period, 511 new cases of Type-2 diabetes emerged. The results suggest that BSSI is the most effective measure for predicting Type-2 diabetes in males, as evidenced by quantile regression curve analyses. In contrast, for women, the predictive abilities of BSSI and BMI are similar and superior to those of BSA. For both sex, BSA was found to be the weakest factor. Notably, BSSI and BMI emerged as the best predictors of Type-2 diabetes, while BSA was identified as the weakest measure for assessing diabetes in adults.