Disclosure control rules
From 2019-20 the SRHAD disclosure control rules were updated in line with the NHS Digital central suppression rules, which have already been assessed and implemented for secondary care and other datasets.
This means that all sub-national counts between 1 and 7 are suppressed, with other sub-national counts rounded to the nearest 5. Sub-national percentage and rate calculations are performed on rounded data and the result shown to the nearest whole number. Calculations based on suppressed counts are also suppressed.
Additionally, where a calculation would be made where the rounded denominator is less than 400, we will not display this result. This is because we cannot be sure that the resulting value (as based on rounded data) is of sufficient accuracy when compared to the 'true' percentage (if based on unrounded data).
For further details see the methodological change notice SRHAD disclosure control methodological change 2019-20
Count of persons
Where ‘persons’ are referred to in the report, a person is only counted once during the year, even if they had multiple contacts with the same service provider. If the same person attends clinics run by different service providers then they will be counted more than once.
Main method of contraception
Where a person contacts a service on multiple occasions during the year, it is necessary to select only one of these contacts as their main contraception method. Prior to 2014/15, this was based on a person’s first contact in the year.
From 2014/15 the methodology was updated, to be based on:
- a person’s final visit to a service in the year where a main method of contraception was identified i.e. if a person’s final visit during the year related to advice or non-contraception related activity only, then this has been discounted from the analysis in favour of an earlier visit, IF in that earlier visit a main method of contraception was recorded.
This method ensures that it reflects the most current main method of a person, and that contacts where a main method of contraception was recorded, are prioritised over non-contraception related contacts.
Compilation of sterilisation and vasectomy data
The following OPCS-4.7 codes classify vasectomy, vasectomy reversal, female sterilisation and female sterilisation reversal:
Procedure codes identifying vasectomies
N17.1 Bilateral vasectomy
N17.2 Ligation of vas deferens NEC
N17.8 Other specified excision of vas deferens
N17.9 Unspecified excision of vas deferens
Procedure codes identifying vasectomy reversals
N18.1 Reversal of bilateral vasectomy
N18.2 Suture of vas deferens NEC
N18.8 Other specified repair of spermatic cord
N18.9 Unspecified repair of spermatic cord
Procedure codes identifying female sterilisations
Q27.1 Open bilateral ligation of fallopian tubes
Q27.2 Open bilateral clipping of fallopian tubes
Q27.8 Other specified open bilateral occlusion of fallopian tubes
Q27.9 Unspecified open bilateral occlusion of fallopian tubes
Q28.1 Open ligation of remaining solitary fallopian tube
Q28.2 Open ligation of fallopian tube NEC
Q28.3 Open clipping of remaining solitary fallopian tube
Q28.4 Open clipping of fallopian tube NEC
Q28.8 Other specified other open occlusion of fallopian tube
Q28.9 Unspecified other open occlusion of fallopian tube
Q35.1 Endoscopic bilateral cauterisation of fallopian tubes
Q35.2 Endoscopic bilateral clipping of fallopian tubes
Q35.3 Endoscopic bilateral ringing of fallopian tubes
Q35.4 Endoscopic bilateral placement of intrafallopian implants
Q35.8 Other specified endoscopic bilateral occlusion of fallopian tubes
Q35.9 Unspecified endoscopic bilateral occlusion of fallopian tubes
Q36.1 Endoscopic occlusion of remaining solitary fallopian tube
Q36.2 Endoscopic placement of intrafallopian implant into remaining solitary fallopian tube
Q36.8 Other specified other endoscopic occlusion of fallopian tube
Q36.9 Unspecified other endoscopic occlusion of fallopian tube
Procedure codes to identify female sterilisation reversals
Q29.1 Reanastomosis of fallopian tube NEC
Q29.2 Open removal of clip from fallopian tube NEC
Q29.8 Other specified open reversal of female sterilisation
Q29.9 Unspecified open reversal of female sterilisation
Q37.1 Endoscopic removal of clip from fallopian tube
Q37.8 Other specified endoscopic reversal of female sterilisation
Q37.9 Unspecified endoscopic reversal of female sterilisation