A body found outdoors has extensive blowfly larval activity. To estimate postmortem interval using forensic entomology, the most reliable primary method is:

• A Identifying the oldest/most-developed larval instar or pupal stage and back-calculating using accumulated degree hours (ADH) ✓
• B Counting the total number of maggots present on the body
• C Weighing the mass of insects collected and dividing by average larval weight
• D Identifying the fly species from adult specimens only, without examining larvae

Explanation

Forensic entomology estimates PMI by identifying the most developmentally advanced stage of the colonising blow fly (typically Calliphora or Chrysomya species in India) and calculating accumulated degree hours (ADH) or accumulated degree days (ADD) — a thermal-time model combining temperature and development time. The oldest larvae represent the first colonisation event, approximating the time of death. Maggot counts and weights do not yield time estimates. Adult fly identification alone, without larval staging, is insufficient.

Reference: The Essentials of Forensic Medicine and Toxicology (Narayan Reddy), 34th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.