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Background information about PROMs

Patient Reported Outcome Measures (PROMs) assess the quality of care delivered to NHS patients from the patient's perspective. Currently covering hip replacement and knee replacement surgery, PROMs calculate the health gains after surgical treatment using pre- and post-operative surveys.

What are Patient Reported Outcome Measures?

PROMs measure a patient's health status or health-related quality of life at a single point in time, and are collected through short, self- completed questionnaires. This health status information is collected before and after a procedure and provides an indication of the outcomes or quality of care delivered to NHS patients and has been collected by all providers of NHS-funded care since April 2009.

Analysis of pre-operative data was released for the first time as an experimental statistic in April 2010, with subsequent monthly updates. In September 2010 analysis of post-operative data was released for the first time, again as experimental statistics. From the August 2011 publication, PROMs data were split by financial year to enable comparison over time and from January 2012, the publication lost its experimental statistics status and was released as Official Statistics.

On 1 October 2017, PROMs data for varicose vein and groin hernia surgery ceased collection, following on from the NHS England Consultation on the future of PROMs.*

Who is responsible for delivering the PROMs programme?


NHS England sets the strategic direction for the national PROMs programme, having taken over responsibility from the Department of Health in April 2013. NHS England is responsible for the decision of what conditions and procedures should be included in the national collection and what measures are used to measure the outcome following treatment.

NHS Digital are commissioned by NHS England to collate, process and publish the data as Official Statistics, and the data is made data available on-line via the NHS Digital website. The Head of Profession for Statistics at NHS Digital is responsible for content, timing and overall assurance of all NHS Digital publications, with each individual publication, including PROMs, also having a responsible statistician accountable for content and quality in each individual area.

PROMs questionnaire services are de-centralised and care providers such as NHS Trusts and independent sector hospitals are free to contract with any approved PROMs questionnaire supplier. As arrangements and standards for data collection are managed by NHS England, companies wishing to offer questionnaire services must first meet these standards before contracting with individual care providers. These standards include holding a current Information Governance toolkit certificate, submitting evidence against each standard and passing test data submission checks.

Casemix adjustment methodology

The case-mix adjustment models were initially developed by the Department of Health and subsequently revised by NHS England. The models are periodically reviewed to ensure that the methodology remains sound over time, the most recent change being made to account the differences between primary and revision procedures for hip and knee replacements.

Before any proposed changes in methodology can be implemented, they must first go through NHS Digital approval process. This covers peer review and oversight from the NHS Digital Methodology Review Group, whose membership includes the Head of Profession for Statistics at NHS Digital as well as the NHS Digital Head of Data Quality.

The MRG then submit their recommendations to the Indicator Governance Board, who must approve the methodology which enables PROMs to be included as part of the Indicator Assurance Service (IAS). PROMs comes under the CCG Outcomes Indicator Set (OIS) Domain 3 (Indicator Portal Code 100761).

Documentation relating to the assurance of PROMs are available from the following links.

What statistics are published, and when?

PROMs data and analyses, are published quarterly by NHS Digital. Each publication contains:

  • an overview of the latest available PROMs data as headline data;
  • a summary of the data quality;
  • a score comparison spreadsheet tool, where the latest available data for provider trusts and clinical commissioning groups can be compared;
  • a mapping tool where provider-level data is presented geographically in a Google Map, and current and historic information is displayed for each of the procedures and various scores;
  • Interactive analytics at provider and CCG level surfaced via Microsoft Power BI;
  • a CSV data pack, which contains several files that enable detailed local analysis, as well as explanatory footnotes. These are:
    • Key Facts, which shows the aggregate number of patients who have improved, unchanged or worsened based on the pre- and post- operative questionnaires for each procedure and measure;
    • Participation Linkage, which shows numbers of participants, linked episodes and questionnaire issue and response rates for each procedure and measure;
    • Provider Commissioner, which shows the number of modelled records, the average pre- and post-operative questionnaires scores and average health gain, the adjusted post-operative score and health gain, as well as the aggregate number of patients who have improved, unchanged or worsened for each procedure and measure;
    • Record-level data for each procedure, which includes one row for each patient questionnaire record successfully linked to a record of inpatient hospital activity in the Hospital Episode Statistics data warehouse.
    • Time series data for each procedure and measure

On an annual basis, the data for the previous financial year are finalised. In addition to the files available each quarter, the finalised release includes a summary PDF report and an equalities file which analyses PROMs data by different demographic groups such as age, sex and deprivation status.

The NHS.UK website also use the full data to update their directory.

Most publications are issued on the second Thursday of the month in February, May, August and November.

Visit the NHS Digital publication calendar to see the set dates for all publications.

How does PROMs work?

PROMs measure a patient's health status or health-related quality of life at a single point in time, and are collected through short, self- completed questionnaires. This health status information is collected before and after a procedure.

Pre-operative questionnaires are offered to all patients undergoing one of the four procedures at an NHS trust or a private trust doing work for the NHS. Completion of the questionnaire is completely voluntary. The procedure should take place within 18 weeks of the questionnaire being completed or a second questionnaire should be offered to the patient closer to the date of treatment.

Post-operative questionnaires are sent out to the patient's home address by one of the accredited PROMs data suppliers on behalf of the provider trust. Before sending this questionnaire, a reasonable time is allowed for the patient to feel the effects of the procedure; generally at least 3 months for groin hernia and varicose vein surgeries, and 6 months for hip and knee replacements. If patients do not complete a post-operative questionnaire within a certain time, data suppliers will send reminders and an additional questionnaire to the patient. These are then returned to the suppliers, who update NHS Digital monthly with the latest data they have.

Given that not all patients can respond right away, we also allow time for the post-operative questionnaires to be sent in after the six month period, which is one of the reasons why the data are not finalised until a year after the reporting period.

Patients are entitled to withdraw their consent to participate in PROMs at any point. Notice of withdrawal of patient's consent may be given in writing to the supplier or via telephone or email helplines, details of which are made available by the suppliers.

What does the information tell us?

PROMs provides an indication of the outcomes or quality of care delivered to NHS patients that enables providers, commissioners and other stakeholders to make informed changes to the delivery of their services. These changes aim to improve outcomes and measurable benefits. PROMs also enables patients to make informed choices about their care. Data are statistically adjusted to ensure that comparisons between provider organisations are robust.

NHS England and the Department of Health also use the data to monitor progress towards strategic objectives, such as those specified in the NHS Outcomes Framework (NHSOF).

Find out more

For more information and help using the PROMs data, please see our PROMs User Guide (video tutorials).

For information on the methodology behind PROMs, please see our PROMs Methodology over-view.

You can also read our PROMs Clinical Case Study or email (citing 'PROMs' in the subject line)

Last edited: 25 March 2021 4:59 pm