Sandeep Sachdeva's research while affiliated with Post Graduate Institute of Medical Sciences, Rohtak and other places

Sir, Socioeconomic status (SES) is one of the most important social determinants of health and disease, thus, widely studied constructs in the social sciences. Usually composite scales are used to measure SES, which has a combination of social and economic variables. Several ways of measuring SES have been suggested for categorizing different rural and urban populations in last decades. The most widely used scale for urban populations is Kuppuswamy's socioeconomic scale, which was devised by Kuppuswamy in 1976. Kuppuswamy scale is a composite score of education and occupation of the head of the family along with monthly income of the family, which yields a score of 3‑29. This scale classifies the study populations into high, middle, and low SES [Table 1]. (1) Usually education and occupation of head of family are not changeable with time. However, the income ranges in the scale lose their relevance following the depreciation in the value of the rupee. (2) Steady inflation, lower interest rates, and country's current account deficits are the main factors contributing to fall in the value of currency. Therefore, it is needed to update the scale regularly for socioeconomic classification of study populations. In the past, Kumar (3) had tried to update Prasad Scale's income limits using consumer price index (CPI) as a first attempt of its kind. In this letter, we attempted to link income limits of the Kuppuswamy socioeconomic scale with CPI and revised the scale. Such linking of the scale with price index not only makes it relevant and meaningful but also provides a built in opportunity for its constant updating in future. The family income per month (in rupees) for 1976 was calculated according to base year 1960 = 100 (using the