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The Administrative Data Research Network is an ESRC-funded project that ran from October 2013 - July 2018. It is currently at the end of its funding cycle and is no longer taking applications. Administrative data research will be taken forward in a new project, to be launched later in 2018.

SMR00 – Outpatient Attendance dataset, 1997-

Title Details

SMR00 – Outpatient Attendance dataset, 1997-
Principal investigator(s):
Information Services Division - NHS National Services Scotland
Data collector(s):
Information Services Division - NHS National Services Scotland

Subject Categories

  • Health services and medical care - Health


  • Abstract copyright ADRN.

    The Outpatients (SMR00) dataset collects episode level data from patients on new and follow up appointments at outpatient Scottish clinics in all specialities (except A&E and Genito-Urinary Medicine) from 1997. The dataset contains patient identifiers (such as name, date of birth, Community Health Index number, NHS number) as well as postcode, ethnicity, clinical speciality, appointment management data and attendance status (e.g. ‘did not attend’) data. Operation / procedure information is also collected. A wide variety of geographical measures are also included in the dataset including the Scottish Index of Multiple Deprivation and Carstairs measures, census output area, NHS Board, Electoral Ward and Parliamentary constituency.

    The dataset is part of a wide range of health related administrative data collected by the Information Services Division (ISD), on behalf of the NHS National Services Scotland (part of NHS Scotland). ISD has been the authoritative source of Scottish national healthcare statistics for over 50 years. The data is used to enhance decisions about Scottish health care to improve the health of the people of Scotland. ISD is part of the SHIP (ScottisH Informatics Programme), a Scotland wide research platform for the collation, management, dissemination and analysis of Electronic Patient Records. As part of SHIP, ISD delivers Electronic Data Research and Innovation Service (eDRIS), a one stop shop for health research designed to provide a single point of contact and to assist researchers in study design, approvals and data (non-patient or patient identifiable) access in a secure environment (the NSS National Safe Haven).

    The Outpatient Attendance dataset covers all people offered a new or follow up outpatient appointment at a Scottish NHS hospital. In England and Wales, the NHS Information Centre collects similar information. In Northern Ireland, the Hospital Information Branch of the Department of Health, Social Services and Public Safety do likewise.

    The Outpatient Attendance dataset began in the early 1990s and the data is routinely available from 1997. The recording of outpatient procedures became mandatory on the 1st April 2003. Health Boards supply data to ISD on a continual basis throughout the year and have targets to submit their data within six weeks. The dataset is generally fully complete and ready for analysis three month preceding the current date. So for example at the end of August, data is available until the end of May.

    The following geographical classes are available in the Outpatients dataset:

    • NHS Board of Residence
    • Council Area
    • Local Government District
    • UK Parliamentary Constituency
    • Scottish Parliamentary Constituency
    • Electoral Ward
    • NUTS
    • Community Health Partnership
    • Data Zone
    • 2001 Census Output Area
    • 1991 Census Output Area
    • Postcode
    • OS Grid References
    • Urban / Rural Codes
    • Scottish Index of Multiple Deprivation measures
    • Carstairs Deprivation 2001
    • Carstairs Deprivation 1991

    On April 1st 2006 the configuration of NHS Boards was changed with NHS Argyll & Clyde being dissolved. The larger part of its area moved into NHS Greater Glasgow with the remainder moving to NHS Highland.

    The definition of an outpatient is someone who attends a consultant or other medical clinic, or has an arranged meeting with a consultant or a senior member of his team outwith a clinic session. A clinic may be held in a hospital outpatient department, a health centre or any other location. An outpatient does not stay in the hospital overnight. A day case patient is different from an outpatient in that although both do not remain in hospital overnight, a day case patient requires the use of a bed, or trolley in lieu of a bed.

    The definition of an outpatient new appointment is the first outpatient appointment that the patient has with a particular consultant for a particular condition. A return appointment is either:

    • A follow-up appointment after a first attendance (with same consultant) with or without an inpatient / day case episode between new and return, or between one return appointment and the next.
    • The first or subsequent outpatient appointment after an inpatient / day case episode with the same consultant.

    Up to four pairs of operation / procedure codes can be recorded on each episode of care. However, recording of procedures only became mandatory on the 1st April 2003. Further information on the types of operations and procedures commonly recorded in the Outpatient dataset is available in the Documentation section.

    In April 1996 diagnostic codes changed from ICD9 to ICD10. Further information on ICD10 is also available in the Documentation section.

    The ISD Data Quality Assurance team is responsible for and ensuring SMR datasets are accurate, consistent and comparable across time and between sources.

    The Outpatient dataset is only considered to be complete for new appointments at consultant-led clinics only. There has been provision to record procedures on Outpatients (SMR00) since 1997, but the level of recording was originally very low. A short list of mandatory procedures was then introduced, and the recording of all procedures became mandatory on the 1st April 2003. However, procedure recording remains an area of data development and there is inconsistency in recording practice between NHS Boards over time. As at 2012, around 150,000 procedures a year are now recorded. Note that it is mandatory for hospitals to submit an Outpatients record for return patients only when a procedure is carried out.

    The ISD Data Quality Assessment team is responsible for evaluating and ensuring all SMR datasets are accurate, consistent and comparable across time and between sources. There are no known, major systematic data quality issues, but it is always wise for researchers unfamiliar with the data to check with their data suppliers and to raise any questions about data quality. Note that, in general, more recent data from ISD is likely to be of higher quality than that of, say, the 1960s. In 2009, a new patient management system was also introduced. This also affected the amount of SMR returns made by NHS Boards.

    The Outpatients dataset was originally set up to collect information on appointments at consultant led clinics. From 1st April 2003, provision was made so that hospitals could also submit information at nurse-led clinics, but this not a mandatory requirement.

    On 1st January 2008 new ways of defining and measuring waiting times came into effect. This introduced a significant change in how the NHS Scotland collected and defined waiting times, and also how waiting lists are clinically and administratively managed.

    Research Usage and Linkage

    The Outpatient dataset is used for a wide variety of purposes by NHS Scotland and the Scottish Government for the purposes of monitoring, performance management and service planning to ultimately improve health care services and patient experience. For example, monitoring the rate of patients who did not attend their appointments across the range of clinical specialties allows boards and service managers to target problem areas and subsequently improve efficiency. The Outpatient dataset is also used for a wide variety of health and epidemiological research purposes.

    It is more difficult to link the Outpatient Attendance dataset with other dataset due to the low level of completeness for the CHI number and other patient identifier fields. As at January 2012, 77% of SMR00 records include a CHI number.

    The SMR00 is not routinely linked by ISD but ad-hoc linkages have been made to the Inpatient and Day Case (SMR01) dataset and the Scottish Morbidity Database.

    The ISD Scotland Medical Record Linkage team could potentially link the Outpatient Attendance dataset with other external data sources, and Privacy Advisory Committee (PAC) approval will be required if using patient identifiable data.

Coverage, universe, methodology

Time period:
1997 -
Observation units:
Events and processes
Kind of data:
Individual (micro) level
All people offered a new or follow up outpatient appointment at a Scottish NHS hospital from 1997.

Time dimensions:
Repeated cross-sectional study
Sampling procedures:
No sampling (total universe)
Number of units:
Approximately 4.4 million records per year (1.6 million new outpatients and 2.8 million return outpatients)
Method of data collection:

Compilation or synthesis of existing material

Health Boards supply data to ISD on a continual basis throughout the year and have targets to submit their data within six weeks.

Frequency of release:
Data Updated:

Administrative and access information

Crown copyright
Access conditions:
Contact the Network



By principal investigator(s):

  • ISD Scotland (2003) Anonymisation and NHS Scotland National Data Sets, ISD Scotland.
  • Scottish Health Informatics Programme (2012) A Blueprint for Health Records Research in Scotland, Scottish Health Informatics Programme.

Resulting from secondary analysis:

  • Williamson, A.E. (2011) Patients repeatedly removed from GP lists:, PhD thesis, University of Glasgow.
  • Burton, C., McGorm, K., Richardson, G., Weller, D., Sharpe, M. (2012) 'Healthcare costs incurred by patients repeatedly referred to secondary medical care with medically unexplained symptoms:', Journal of Psychosomatic Research, 72(3), pp. 242-247. 10.1016/j.jpsychores.2011.12.009

Page last updated: 20/09/2017