Draft safety review: delayed gastric emptying and procedural… — submissions
The 15 submissions received, published in full with declared interests and secretariat responses.
§2Submissions and responses
15 submissions were received. Each is published in full below with its declared interest, the secretariat response and the disposition. The Institute publishes submissions it did not accept in the same form as those it did.
The document should not describe uses outside the approved indication
The submission is made on behalf of a marketing-authorisation holder. It states that the draft describes uses of the compound that fall outside the approved indication, that such uses are not supported by the sponsor, and that describing them may be read as legitimising them.
The sponsor asks that the sections concerned be removed, or in the alternative that they carry a prominent statement that the sponsor does not support such use.
The secretariat does not accept this submission. The Institute records what is supplied and what is used, because a reader encountering a compound outside a regulated route is the reader most in need of an assessment of the evidence for it.
The sections remain. Every such section already states the regulatory status of the use described and states that the evidence for it is assessed separately from the evidence for the approved indication. The submission is published in full and identified as an industry submission.
The search strategy as published cannot be re-run
The strategy is described in prose rather than reproduced as executed. The respondent, an information specialist, attempted to reconstruct it and obtained a different yield, which may reflect the reconstruction or the original.
The respondent proposes that the strategy be published line by line as run in each database, with the interface, the date and the number of records retrieved at each line.
The secretariat accepts this submission. A strategy that cannot be re-run cannot be checked, and a review whose search cannot be checked rests on an assertion.
The full line-by-line strategy for each database is now published with the interface, the run date and the yield at each line, and the total retrieved is reconciled against the screening flow.
A sponsor trial meeting the eligibility criteria was excluded
The submission is made on behalf of the sponsor. It identifies a completed trial of the sponsor's compound that meets the stated eligibility criteria and does not appear in the included set, and supplies the trial report and the registry record.
The sponsor asks that the trial be included and the estimate recomputed. No view is expressed on the direction the recomputation should take.
The secretariat accepts this submission in part. The trial does meet the criteria and has been included. The recomputed estimate is materially unchanged, which the response states explicitly so that the outcome of the correction is on the record.
The trial is added to the included set, the estimate and the certainty rating have been recomputed, and the screening record now states why the trial was missed, which was a database indexing gap rather than a screening judgement. The submission is identified as an industry submission.
Regulatory assessment documents were not searched
The respondent states that regulatory assessment reports frequently contain analyses that never appear in journals, and that a search limited to bibliographic databases will miss them.
The respondent proposes that regulatory documents be searched for every review in the series.
The secretariat accepts this submission in part. Regulatory assessment documents are searched. The proposal that they be treated as equivalent to a full study report is declined, because the level of detail varies and is often insufficient for risk-of-bias assessment.
Published regulatory assessment documents are now searched as a named source, are reported as a distinct evidence class in the included-studies table, and contribute to the assessment while being excluded from pooled estimates where risk of bias could not be assessed from the document.
A surrogate outcome is used as the anchor without validation evidence
The anchor outcome in the draft is a surrogate. The respondent states that the relationship between the surrogate and the outcome a decision turns on is itself an evidential question, and that the draft assumes it.
The respondent proposes that no surrogate serve as an anchor.
The secretariat accepts this submission in part. The anchor is retained where the surrogate is the only outcome the contributing trials measured, and the validation question is addressed rather than assumed.
Where the anchor is a surrogate, the synthesis now states the evidence for the surrogate relationship, rates it separately, and downgrades the anchor rating for indirectness accordingly rather than carrying the surrogate as though it were the outcome of interest.
Patient-reported outcomes are collected by the trials and not reported by the review
The respondent, a trustee of a patient organisation, states that several contributing trials measured quality of life and function and that the review reports neither, having selected outcomes on the basis of what could be pooled.
The respondent proposes that these outcomes be reported narratively where they cannot be pooled.
The secretariat accepts this submission in part. The outcomes are reported narratively. The proposal to pool them is declined because the instruments used are not comparable and pooling would produce a figure with no interpretation.
Patient-reported outcomes measured by any contributing trial are now reported narratively by instrument, with the instrument named and its minimum important difference stated where one is published, and the absence of a pooled estimate explained.
Doses differing several-fold are pooled without examining dose-response
Contributing trials administer doses that differ by a factor of several. The draft pools them and reports one estimate. The respondent states that where a dose-response relationship exists the pooled figure corresponds to no dose that anyone receives.
The respondent proposes that estimates be reported by dose and that dose-response be examined where the data allow.
The secretariat accepts this submission. A pooled estimate across doses is an estimate for an average dose that no protocol specifies.
Estimates are now reported by dose group, a dose-response examination is reported where three or more dose levels contribute, and the pooled across-dose estimate is removed rather than retained alongside.
The search date is not on the face of the document
The draft carries a publication date and a review date but not the date on which the evidence was last searched. Those are three different dates and only the third tells a reader how current the assessment is. A document published in one quarter may rest on a search run two quarters earlier, and nothing on the page allows that gap to be measured.
The respondent proposes that the search date be printed adjacent to every certainty rating rather than in the methods section, on the ground that a reader who acts on a rating is unlikely to have read the methods section first.
The secretariat accepts this submission. The distinction between publication, review and search dates is real and the draft did not make it visible where it mattered.
The search date is now printed adjacent to every certainty rating and is carried in the document metadata, so that the interval between the search and the reading is visible without reference to the methods section.
Risk-of-bias judgements are reported as an overall rating without the domains
The draft reports a single overall risk-of-bias judgement per study. The respondent states that the overall judgement conceals which domain drove it, and that a reader assessing whether the concern applies to their question needs the domain.
The respondent proposes a domain-level table with the supporting quotation for each judgement.
The secretariat accepts this submission. The overall judgement is a summary of the domains and publishing only the summary makes it uncheckable.
Risk of bias is now reported at domain level for every included study, with the text on which each judgement was based quoted and referenced, and the overall judgement derived from the domains rather than asserted alongside them.
Results at materially different follow-up durations are pooled
Contributing trials report the outcome at durations ranging across more than a year. The draft pools them into a single estimate. The respondent states that a mean at one duration and a mean at another are not estimates of the same quantity when the effect is still changing.
The respondent proposes that estimates be reported by duration band.
The secretariat accepts this submission. Pooling across durations assumes a plateau the contributing trials do not demonstrate.
Estimates are now reported by duration band, with the number of contributing trials and participants in each band stated, and no estimate is pooled across bands.
Analytical surveys are treated as evidence about suppliers when they establish only what was in a sample
Several included surveys purchased material anonymously and analysed it. The respondent states that where the chain from a named supplier to the analysed vial cannot be documented, the result describes a sample and not a supplier.
The respondent proposes that provenance be an explicit eligibility dimension, with surveys reported separately according to whether it could be established.
The secretariat accepts this submission. Moderate certainty evidence from the included surveys supports statements about material circulating in a market; it does not support statements about any named supplier's output.
Provenance is now assessed for every included survey and reported as a study characteristic, surveys without establishable provenance are reported separately rather than pooled with those that have it, and no supplier-level inference is drawn from a sample-level result.
Baseline imbalance in a small contributing trial is not remarked on
The respondent identifies a small contributing trial with a baseline difference in the outcome variable, and states that the difference is large enough to account for a share of the reported effect.
The respondent asks that the trial be excluded or that the imbalance be addressed.
The secretariat notes this submission. The imbalance is recorded in the risk-of-bias assessment for that trial, in the domain concerning the randomisation process, where the respondent may not have looked.
No amendment arises. The judgement and the supporting figures are already reported at domain level for that study, and a sensitivity analysis omitting it is reported in the results, which does not change the direction of the estimate.
The document is unreadable without specialist training
The respondent, a trustee of a patient organisation, states that the draft is written for a reader who already understands certainty grading, and that the people most affected by the subject matter will not reach the assessment at all.
The respondent proposes a plain-language summary at the head of every document, written to the same standard of accuracy as the document itself and not as a promotional abstract.
The secretariat accepts this submission in part. A plain-language summary is added. The proposal that it replace the technical abstract is declined, because the abstract is the part of the document other assessors read and cite.
Every document now opens with a plain-language summary of not more than 150 words, placed above the technical abstract and carrying the same certainty language, so that the two cannot diverge.
Efficacy outcomes are rated for certainty and harms are not
The draft assigns certainty ratings to the efficacy outcomes and reports harms narratively without ratings. The respondent states that the asymmetry implies harms are less amenable to assessment when they are simply less well measured.
The respondent proposes that harms carry certainty ratings on the same scale, with the reasons for downgrading stated.
The secretariat accepts this submission. Rating one side of the balance and not the other produces a document that cannot be used to weigh them.
Every reported harm now carries a certainty rating on the same scale as the efficacy outcomes, with the downgrade reasons stated, and discontinuation for adverse events appears in the summary of findings rather than in an annex.
Statistical heterogeneity is treated as though it measured clinical heterogeneity
The draft reports a heterogeneity statistic and proceeds to pool where it is low. The respondent states that a low statistic in a small set of trials is uninformative, and that clinical and methodological similarity should be assessed before any statistic is consulted.
The respondent proposes that the decision to pool be justified on clinical grounds first and that the statistic be reported as a description rather than used as a threshold.
The secretariat accepts this submission in part. The decision to pool is now made on clinical and methodological grounds and stated as such. The statistic continues to be reported, because readers expect it and its absence would be read as concealment.
The decision to pool is now justified in prose against the population, intervention, comparator and outcome before any statistic is presented, and the heterogeneity statistic is reported with its confidence interval and a note of the number of contributing studies.
References cited on this page
References are numbered in order of first citation in this document. Each superscript in the text links to its entry below.
- International Organization for Standardization. ISO/IEC 17025:2017 General Requirements for the Competence of Testing and Calibration Laboratories. ISO/IEC Standard 2017;3rd edition. identifier not held by the Institute
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