Summary of findings 2. Summary of findings: IMRT vs 3DCRT.
| IMRT compared with 3DCRT to reduce adverse GI effects of radiotherapy | ||||||
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Patient or population: People with urological (prostate) and gynaecological (cervical) cancer Settings: Tertiary care setting Intervention: IMRT Comparison: 3DCRT | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality/certainty of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| 3DCRT | IMRT | |||||
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Mean GI symptom scores (EORTC‐QLQPR25 scale; lower scores better) |
At 6 months post‐RT, the mean GI symptom score in the control group was 9 | At 6 months post‐RT, the mean GI symptom score in the intervention group was 4 (1 to 9 points lower) |
MD ‐5.00 (‐9.06 to ‐0.94) |
181 (1) | ⊕⊕⊝⊝ low1, 2 | ‐ |
| Acute and late GI toxicity Grade 2+ | Acute toxicity (up to 3 months post‐RT): 445 per 1000 |
Acute toxicity (up to 3 months post‐RT): 214 per 1000 (116 to 392) |
RR 0.48 (0.26 to 0.88) |
444 (4) | ⊕⊕⊝⊝ low1, 3 | Inconsistency was present between studies in the gynaecological cancer subgroup but not between gynaecological and urological subgroups |
| Late toxicity (from 6 months post‐RT): 228 per 1000 |
Late toxicity (from 6 months post‐RT): 84 per 1000 (48 to 148) |
RR0.37 (0.21 to 0.65) |
332 (2) | ⊕⊕⊝⊝ low4 | Findings were consistent across gynaecological and urological subgroups. | |
|
Diarrhoea (grade 2+) |
Acute toxicity (up to 3 months post‐RT): 720 per 1000 |
Acute toxicity (up to 3 months after RT): 273 per 1000 (158 to 490) |
RR 0.38 (0.22 to 0.68) |
72 (1) | ⊕⊕⊝⊝ low1, 5 |
‐ |
| QoL scores | ‐ | ‐ | Not estimable | 0 | ‐ | No data |
| *The basis for the assumed risk is the mean control group risk across studies. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: Confidence interval; RR: Risk Ratio; MD: mean difference; QoL: quality of life | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1Downgraded one level for design limitations (unclear risk of bias). 2Downgraded for imprecision (evidence based on continuous data from one study of 181 participants). 3Downgraded for inconsistency across studies (I2 = 77%). 4Downgraded two levels for design limitations as the analysis includes data from Viani 2016 (51.8% weight), which were imputed from percentages and considered at high risk of bias for this outcome, and one study considered to have an unclear risk of bias. 5Downgraded one level for imprecision (evidence is based on 71 participants from one small study).