The formalin test in the mouse: a parametric analysis of scoring properties
Bibliographic record
Abstract
We investigated the scoring properties of the mouse formalin test using the time-sampling method recently developed for infant and adult rats. Formalin was injected under the plantar surface of one rear paw (10 microl, 1-8%), and pain behaviours (paw favouring, lifting and licking) and behavioural state were recorded. Correlational and regression analyses indicated that scores composed of combinations of all three pain behaviours, either summed or weighted, provided less variable indices of pain than licking alone. The maximum percent effect (MPE(50); i.e. pain behaviour 50% of the time) for the log formalin concentration-effect curves was 3-4% in both phases. Habituation to the test environment prior to testing did not alter the MPE(50)s, but slopes were lower in unhabituated mice, dramatically increasing the size of the confidence interval. Formalin dose-dependently reduced locomotion, rearing and sniffing in both the first phase and the early part of the second phase. The combination measures were sensitive to morphine (2-8 mg/kg), amphetamine (1-4 mg/kg), dipyrone (50-200 mg/kg), xylazine (0.25-1 mg/kg), and acepromazine (0.25-1 mg/kg), and resistant to diazepam (0.5-2 mg/kg), pimozide (0.05-0.25 mg/kg), pentobarbital (10 and 15 mg/kg) and indomethacin (2-8 mg/kg). Decreased pain was correlated with increased motor activity for morphine and amphetamine, and with decreased activity for xylazine and acepromazine; dipyrone and indomethacin did not alter activity levels.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.006 | 0.012 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".