PMI Correction
Definition
Adjustment of the post-mortem interval estimate to account for documented drug or toxin effects on larval development rate. Without correction, a drug-accelerated larva makes death appear more recent than it was.
- Field
- Forensic entomology, entomotoxicology
- Adjusts for
- Drug or toxin effect on larval growth rate
- Uncorrected error
- PMI appears shorter than actual
Common questions
Which drugs typically require a PMI correction?+
Stimulants such as cocaine and methamphetamine are the best-documented accelerants of larval development, while some central nervous system depressants can slow growth instead, so the direction and size of the correction depends on the specific substance found in the tissue.
How does an entomologist know a correction is needed?+
Toxicological analysis of the larvae or the remains identifies the drug present, and published rearing studies for that species and substance combination supply the growth-rate offset applied to the standard development-time-to-PMI calculation.
Related terms
- Bioaccumulation in Insects
- The uptake and concentration of a toxicant from the substrate (decomposing tissue) into insect tissues during larval feeding. Concentration in larval tissue...
- Development Rate Alteration
- A drug- or toxin-induced shift in the time from oviposition to pupation. Stimulant compounds tend to accelerate development; certain heavy metals and...
- Empty Puparium
- The hardened larval skin (puparium) left behind after adult emergence. It retains chemical residues including drug metabolites and can be the only...
- Entomotoxicology
- The analysis of insect tissue for drugs and toxins when decomposition has made conventional biological fluids unavailable. Blow-fly larvae feeding on a...
- Larval Crop Contents
- The partially digested material in the larval foregut, reflecting the most recent substrate the larva fed on. Useful for detecting what the...