Performance Indicator 16: Positive predictive value of colposcopy
Summary positive predictive value of colposcopy data
The positive predictive value of colposcopies performed in 2023 for participants aged 25–74 was 66.0%.
Positive predictive value of colposcopy
Definition
Percentage of participants aged 25–74 with a higher risk screening or follow-up episode result who had a colposcopic impression of HSIL, glandular abnormality (adenocarcinoma in situ) or cancer in a calendar year who were diagnosed with a high-grade abnormality or cervical cancer on histology within 6 months of colposcopy.
Rationale
This indicator correlates the colposcopic impression with histological findings to determine the predictive value of colposcopy for high-grade cervical abnormalities. This is an important measure of the quality of colposcopy.
Data considerations
Colposcopy data in the NCSR come from several sources. One source is the colposcopy form, which includes information on the colposcopy itself and colposcopic impression. While colposcopy data are also sourced from MBS, this level of information is not available for colposcopies for which MBS is the only data source. Therefore, the positive predictive value of colposcopy is calculated using only colposcopies for which the source of data is a colposcopy form.
This indicator looks at positive predictive value of colposcopy after higher risk results. Prior to 1 February 2021, there were three groups of higher risk participants – two based on primary screening episode results and one based on the follow-up HPV test performed 12 months following an intermediate risk primary screening episode.
Since 1 February 2021, there are four groups of higher risk participants – the same two based on primary screening episode results, one based on the first follow-up screening episode results (including those that would otherwise be intermediate risk but are assigned to higher risk due to being under-screened, Aboriginal and/or Torres Strait Islander, or aged 50 or over), and one based on the second follow-up screening episode.
This performance indicator is based on colposcopies performed in 2023.
This allows 6 months to 30 June 2024 to know if they were diagnosed with a high-grade abnormality or cervical cancer within 6 months, and a further 6 months to 31 December 2024 to ensure that histology data to 30 June 2024 are complete.
Results
The positive predictive value of colposcopy includes all colposcopies performed after a higher risk screening or follow-up test with a colposcopic impression of high-grade abnormality or cervical cancer.
Of the participants aged 25–74 who had a colposcopy in 2023 with a colposcopic impression of high-grade abnormality or cervical cancer following a higher risk screening or follow-up test, 66.0% had a high-grade abnormality or cervical cancer detected on histology within 6 months of the colposcopy. This is the positive predictive value of colposcopy.
This differed according to the higher risk screening or follow-up result that preceded the colposcopy. The positive predictive value of colposcopy was highest for participants whose primary screening HPV test detected oncogenic HPV (not 16/18) and whose LBC test result was a high-grade squamous abnormality, squamous cell carcinoma, or a glandular abnormality at 77.1% (Table 16.1).
The positive predictive value of colposcopy was next highest for participants whose first follow-up HPV test detected oncogenic HPV 16/18 or whose first follow-up HPV test detected oncogenic HPV (not 16/18) and whose reflex LBC test result was a high-grade squamous abnormality, squamous cell carcinoma, or a glandular abnormality (or whose first follow-up HPV test result was oncogenic HPV (not 16/18) and whose reflex LBC test result was negative or a low-grade squamous abnormality and were under-screened, Aboriginal and/or Torres Strait Islander, or aged 50 or over) at 63.2% and participants whose primary screening HPV test detected HPV 16/18 at 63.0%.
The positive predictive value of colposcopy was lower for participants whose second follow-up HPV test detected any oncogenic HPV at 55.0% (Table 16.1).
Screening or follow-up result | Number | Positive predictive value (%) |
|---|---|---|
Primary screening test HPV 16/18 + any LBC | 685 | 63.0 |
Primary screening test HPV (not 16/18) + high-grade/glandular LBC | 722 | 77.1 |
First follow-up test HPV 16/18 + any LBC or HPV (not 16/18) + high-grade/glandular LBC | 240 | 63.2 |
Second follow-up test any HPV + any LBC | 298 | 55.0 |
Total | 1,945 | 66.0 |
Source: AIHW analysis of NCSR data (NCSR RDE 11/07/2025).
The positive predictive value of colposcopy for each squamous and endocervical LBC test result from the higher risk screening or follow-up test that preceded the colposcopy was also calculated. Positive predictive value of colposcopy was found to increase with increasing severity of abnormality, and was highest at 100.0% for LBC test results of squamous cell carcinoma, and 94.1% for LBC test results of adenocarcinoma in situ or adenocarcinoma (Table 16.2).
LBC test result | Number | Positive predictive value (%) |
|---|---|---|
S1 negative | 111 | 30.6 |
S2 possible low-grade squamous intraepithelial lesion | 51 | 38.9 |
S3 low-grade squamous intraepithelial lesion | 111 | 50.5 |
S4 possible high-grade squamous intraepithelial lesion | 570 | 69.0 |
S5 high-grade squamous intraepithelial lesion | 733 | 86.3 |
S6 or S7 high-grade squamous intraepithelial lesion with possible invasion or squamous cell carcinoma | 51 | 100.0 |
E2 atypical endocervical cells of uncertain significance | 20 | 76.9 |
E3 possible high-grade endocervical glandular lesion | 16 | 88.9 |
E4, E5, or E6 adenocarcinoma in situ, adenocarcinoma in situ with possible invasion, or adenocarcinoma | 16 | 94.1 |
Note: This table includes each squamous and endocervical result in isolation, not as a pair, so where there is a high-grade abnormality or cervical cancer within 6 months of a negative squamous result, there may have been a glandular abnormality in the endocervical result.
Source: AIHW analysis of NCSR data (NCSR RDE 11/07/2025).
Positive predictive value of colposcopy by age
The positive predictive value of colposcopy is shown by age in Figure 16.1. This tended to be higher in participants aged under 55 and lower for those aged over 55.
Figure 16.1: Positive predictive value of colposcopy, by age, 2023
Source: AIHW analysis of NCSR data (NCSR RDE 11/07/2025). Data and notes for this figure are available in Table A16.1.
Positive predictive value of colposcopy trends
The positive predictive value of colposcopy was around 68% for the years 2018 to 2020. Following the introduction of a second follow-up episode and the addition of a new higher risk group, the positive predictive value of colposcopy initially increased to 70.5% in 2021, then fell to 69.9% in 2022 and 66.0% in 2023 (Figure 16.2).
Figure 16.2: Positive predictive value of colposcopy, by year, participants aged 25–74, 2018 to 2023
Source: AIHW analysis of NCSR data (NCSR RDE 11/07/2025). Data and notes for this figure are available in Table A16.2.