Development and validation of <scp>IHS4</scp>‐55, an <scp>IHS4</scp> dichotomous outcome to assess treatment effect for hidradenitis suppurativa
Bibliographic record
Abstract
BACKGROUND: Validated, inclusive and easy-to-use outcomes for hidradenitis suppurativa are essential both in the clinical trial setting and clinical practice. The continuous IHS4 is a validated tool that dynamically assesses nodules/abscesses/draining tunnels and classifies disease severity as mild/moderate/severe. However, dichotomous outcomes are often required for clinical trials reporting. OBJECTIVE: To develop and validate a dichotomous outcome based on IHS4 that can be used in clinical trial settings and day-to-day clinical practice. METHODS: De-identified data from the PIONEER-I and -II studies were accessed through Vivli. Potential IHS4 thresholds were analysed using baseline to Week 12 data from adalimumab- and placebo-treated hidradenitis suppurativa patients in the PIONEER-I trial. The final threshold was chosen based on its ability to discriminate between patients treated with adalimumab or placebo and its association with reduction in inflammatory lesions. The final threshold was validated using data from baseline to Week 12 from adalimumab- and placebo-treated hidradenitis suppurativa patients in both the PIONEER-II and the combined PIONEER-I and -II studies. RESULTS: The best performing cut-off for the IHS4 was a 55% reduction of the IHS4 score (IHS4-55). Patients who achieved the IHS4-55 had an odd's ratio of 2.00 [95%-CI 1.26-3.18, p = 0.003], 2.79 (95%-CI 1.76-4.43, p < 0.001) and 2.16 (95%-CI 1.43-3.29, p < 0.001) for being treated with adalimumab rather than placebo in PIONEER-I, PIONEER-II and the combined dataset, respectively. Additionally, the achievement of the IHS4-55 was associated with a significant reduction in inflammatory nodules, abscesses and draining tunnels in all analysed datasets. CONCLUSIONS: IHS4-55, a novel dichotomous IHS4 version, based on a 55% reduction of the total score was developed. The IHS4-55 performs similarly to the HiSCR in discriminating between adalimumab- and placebo-treated hidradenitis suppurativa patients and shows significant associations with reductions in lesion counts. Moreover, the IHS4-55 addresses some of the HiSCR drawbacks by dynamically including draining tunnels in a validated manner. By allowing the analysis of hidradenitis suppurativa patients with an abscess and nodule count below 3 but many draining tunnels, this outcome measure will improve inclusivity in clinical trials.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.066 | 0.077 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.003 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.003 | 0.001 |
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".