per-protocol
UK[pɜː ˈprəʊtəkɒl]US[pər ˈproʊtəkɔːl]
adj
Relating to or following the specific, predefined procedures and criteria of a study or trial, especially in contrast to an analysis that includes all participants regardless of adherence.
adj
Conducted or analyzed strictly according to the original, planned methodology.
Morpheme Breakdown
per
protocol
per
through
protocol
plan
Etymology
The term is a modern compound, primarily used in scientific and clinical research contexts. The prefix "per", from Latin, carries its core meaning of "through" or "thoroughly", here emphasizing strict adherence. The base word "protocol" has a long journey from the Greek 'protokollon' (the first sheet of a papyrus roll, containing authentication details), evolving through Late Latin and French to denote official formulas and, by the 20th century, a detailed plan for a scientific experiment. Thus, "per-protocol" literally means "through the plan", logically evolving to describe an analysis that meticulously follows the trial's original blueprint, excluding any data from participants who deviated from it.
Analysis
Structure: per (through) + protocol (plan)
per: Latin origin, meaning "through", "by", or "thoroughly". In this compound, it functions as an intensifying prefix meaning "thoroughly" or "strictly according to".
protocol: From Greek 'protokollon' (first sheet glued to a manuscript), via Late Latin and French. It functions as the base noun meaning the original plan or set of rules.
Examples
The per-protocol analysis showed a stronger treatment effect than the intention-to-treat analysis.
Results were consistent across both the intention-to-treat and per-protocol populations.
Participants with major protocol violations were excluded from the per-protocol assessment.