| Verified against primary record | |
| Definition | Any report of the status of a patient’s health condition coming directly from the patient, without interpretation by a clinician or anyone else[1] |
|---|---|
| Also known as | PROMs |
| English national programme | Hip and knee replacement; groin hernia and varicose vein collection ceased 1 October 2017[2] |
| Instruments used | Oxford Hip Score, Oxford Knee Score, EQ-5D index and EQ visual analogue scale[3] |
| Participation, 2021-22 | 70.1 per cent for hip and 68.3 per cent for knee at the pre-operative stage[4] |
| Records read | Two regulatory definitions and four national programme publications, 2 October 2026 |
| Independently reported | |
| Scope | No national PROMs collection covering privately funded treatment abroad was located |
| Bands apply only to the rows beneath them. Scoring direction and scale ranges for the named instruments were not verified and are not stated here. | |
Patient-reported outcome measures, usually abbreviated to PROMs, are questionnaires completed by patients themselves about their own health status, administered before and after treatment so that the change can be measured. They are the closest thing in routine health statistics to an answer to the question of whether an operation worked, and their absence from medical travel is the most consequential evidence gap in the sector.
What makes a measure a PROM
The regulatory definition is narrow and useful. A patient-reported outcome is any report of the status of a patient’s health condition that comes directly from the patient, without interpretation of the patient’s response by a clinician or anyone else.[1] A clinical registry handbook puts it as a measurement based on a report that comes directly from the patient, without amendment or interpretation.[5] A surgeon’s assessment of a result is therefore not a PROM, however carefully recorded.
An instrument has to earn its use. Reliability is established through reproducibility such as test-retest reliability and internal consistency tests such as Cronbach’s alpha; content validity is the extent to which the instrument measures the concept of interest; construct validity and responsiveness, meaning evidence that the instrument can identify differences in scores over time, complete the set.[1] The registry handbook gives the same properties in parallel terms, defining reliability as the ability of an instrument to yield the same result on serial administrations when no change in the concept being measured is expected, criterion validity as the extent to which scores reflect a gold standard measure, and responsiveness as the ability to detect change.[5]
One feature of the method is often overlooked and matters when results are compared. There is no universal threshold for a meaningful change. The regulator’s approach is to establish responder definitions using anchor-based methods and distribution-based methods, determined empirically, which may vary by target population.[1] A score improvement is therefore interpretable only against a threshold derived for that instrument in that population.
The English national programme as a working example
England operates the longest-running national PROMs collection, and its mechanics show both what the method can deliver and where it stops. The programme assesses the quality of care delivered to NHS patients from the patient’s perspective. Pre-operative questionnaires are offered to all patients undergoing one of the covered procedures at an NHS trust or a private trust doing work for the NHS, and completion is entirely voluntary. Post-operative follow-up is generally at least six months for hip and knee replacements. Groin hernia and varicose vein surgery were covered until collection ceased on 1 October 2017.[2]
Each procedure has a condition-specific instrument, the Oxford Hip Score for hip procedures and the Oxford Knee Score for knee procedures, alongside a generic health status instrument, the EQ-5D, included in all national questionnaires, and a visual analogue scale. The programme’s stated purpose is to collect information, from patients themselves, about how well the health service is treating them.[3] The resulting dataset is linked to the national hospital episode data warehouse and published as official statistics, the 2022-23 release appearing on 12 December 2024.[6]
Attrition at four stages
The published engagement figures are the most instructive part of the programme, because they show how a voluntary paired-questionnaire design shrinks a national caseload into an analysable sample. For hip replacement in 2021-22 there were 68,335 NHS-funded procedures, 47,872 pre-operative questionnaires returned, a participation rate of 70.1 per cent, up from 67.1 per cent, a linkage rate of 58.0 per cent, a post-operative response rate of 63.1 per cent, and 16,980 records with both questionnaires completed. For knee replacement there were 74,082 procedures, 50,616 returned, participation of 68.3 per cent, up from 66.0 per cent, linkage of 59.4 per cent, a post-operative response rate also reported as 59.4 per cent, and 17,049 complete pairs.[4]
Roughly a quarter of procedures end up with a usable pair of questionnaires. That is not a criticism of the programme, which publishes the attrition openly, but it is the context for any health gain figure derived from it. For knee replacement in 2021-22 the published average health gains were 17.3 on the Oxford Knee Score, 0.326 on the EQ-5D index and 8.0 on the visual analogue scale across all procedures, with 17.6, 0.326 and 8.5 for primary procedures and 14.1, 0.311 and 7.3 for revisions.[7]
Two arithmetic points in the 2021-22 engagement tables are noted for the record. The hip linkage figure is expressed against 47,827 questionnaires while the returns figure given elsewhere on the same page is 47,872, a difference of 45 records. And the knee linkage rate and post-operative response rate are both reported as 59.4 per cent.[4] Neither materially affects the health gain results, and neither is resolved here.
Why medical travel generates no PROM
The design features described above define the population that can enter the dataset, and they exclude treatment abroad by construction rather than by policy. The pre-operative questionnaire is offered at the provider at the point of NHS-funded treatment, and the record is identified by linkage to the national hospital episode warehouse. A patient who flies abroad and pays privately generates no domestic hospital episode, is offered no pre-operative questionnaire by any provider, and therefore has no baseline against which a later score could be compared.
The result is that for the procedures most commonly sought abroad there is no equivalent of the English health gain figures at all, and no mechanism by which one could currently be produced. A destination provider could in principle administer a validated instrument before and after treatment and publish the paired results. None found for this site does so.
See also
- Patient-reported experience measures, the parallel instruments measuring the process of care
- Patient satisfaction in medical tourism, what is collected instead
- Orthopedic medical travel, the procedures the English programme covers
- Administrative data in medical tourism research, the linkage the programme depends on
References
- United States Food and Drug Administration. Guidance for industry: patient-reported outcome measures, use in medical product development to support labeling claims. December 2009. Verified against primary record: definition, measurement property and responder definition sections read. Retrieved 2 October 2026.
- NHS England Digital. Background information about PROMs. Verified against primary record: programme scope, voluntary participation and follow-up intervals read. Retrieved 2 October 2026.
- NHS England. Patient reported outcome measures, a guide. Version 3, August 2018. Verified against primary record: instrument list and stated purpose read. Retrieved 2 October 2026.
- NHS England Digital. Finalised PROMs, hip and knee replacement, April 2021 to March 2022: patient engagement. Verified against primary record: procedure counts, participation, linkage and response rates read in full. Retrieved 2 October 2026.
- Gliklich RE, Dreyer NA, Leavy MB, editors. Registries for evaluating patient outcomes: a user’s guide. Third edition, Agency for Healthcare Research and Quality, 2014. Verified against primary record: definitions of patient-reported outcome, reliability, criterion validity and responsiveness read. Retrieved 2 October 2026.
- NHS England Digital. Finalised PROMs, 2022-23: introduction. Published 12 December 2024. Verified against primary record: publication status, instruments and data linkage read. Retrieved 2 October 2026.
- NHS England Digital. Finalised PROMs, April 2021 to March 2022: average health gain, knee replacement. Published 13 July 2023. Verified against primary record: health gain values read from the published table. Retrieved 2 October 2026.
Sourcing note: the regulatory guidance, the registry handbook and the four national programme publications were opened and read on 2 October 2026. Only knee replacement health gain figures are published here, because the corresponding hip page was not opened. Scoring direction, scale ranges and the internal structure of the generic instrument are not stated, because no authoritative source for them was read for this entry. The absence of PROMs for treatment abroad is a conclusion drawn from the programme’s stated eligibility and linkage rules; no source states it directly.