Methodological quality of systematic reviews on atopic dermatitis treatments: a cross-sectional study

Figures & data

Figure 1. Flow of literature selection.

Table 1. Bibliographical characteristics of the 52 included systematic reviews on atopic dermatitis treatments.

Bibliographical characteristics	Results*^,†
Cochrane review	6 (11.5)
An update of a previous systematic reviews	7 (13.4)
Systematic reviews reporting intervention harms	37 (71.2)
Systematic reviews that searched English databases	52 (100)
Systematic reviews that searched non-English databases	18 (34.6)
Included a PRISMA-like flow diagram	49 (94.2)
Publication journal impact factor median (range)	4.35 (0–14.71)
Number of review authors median (range)	5 (2–26)
Number of included primary studies
Total	973
Median across the systematic reviews (range)	13.5 (4–104)
Number of participants included in primary studies
Total	516830
Median across the systematic reviews (range)	2093 (0–385901)^‡
Location of corresponding author
Europe	12 (23.1)
America	7 (13.5)
Asia	31 (59.6)
Oceania	1 (1.9)
Africa	1 (1.9)
Funding location of systematic review
Europe	10 (19.2)
America	4 (7.7)
Asia	13 (25.0)
Oceania	0 (0)
Africa	1 (1.9)
Not reported	24 (46.2)
Type of interventions
Pharmacological	42 (80.8)
Non-pharmacological	7 (13.5)
Both	3 (5.8)
Reported year of coverage of literature search	51 (98.1)
Search terms reported for one or more electronic databases
Topics/free text/keywords/MeSHs	26 (50.0)
Full Boolean	24 (46.2)
Readers are referred elsewhere for full search strategy	1 (1.9)
No research terms	1 (1.9)
Language of included primary studies in the systematic reviews
English only	22 (42.3)
Language other than English	0 (0)
English and languages other than English	30 (57.7)
Language criteria not reported	0 (0)
Tools for assessing quality of primary studies
Cochrane risk of bias	37 (71.2)
Jadad scale	1 (1.9)
More than one tool	6 (11.5)
Not reported	8 (15.4)

MeSHs: Medical Subject Headings; PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-analysis.

* Values are N (%), or median (range).

^† Percentages were calculated by using the total number of the categories as the denominator.

^‡ 0 due to missing data.

Table 2. Results of the AMSTAR2 domain items for the 52 included systematic reviews on atopic dermatitis treatments.

AMSTAR 2 items	Yes (%)	Partial Yes (%)	No (%)
1. Did the research questions and inclusion criteria for the review include the components of PICO?	52 (100)	NA	0 (0)
2. Did the report of the review contain an explicit statement that the review methods were established prior to the conduct of the review and did the report justify any significant deviations from the protocol?*	21 (40.4)	3 (5.8)	28 (53.8)
3. Did the review authors explain their selection of the study designs for inclusion in the review?	0 (0)	NA	52 (100)
4. Did the review authors use a comprehensive literature search strategy?*	5 (9.6)	21 (40.4)	26 (50.0)
5. Did the review authors perform study selection in duplicate?	39 (75.0)	NA	13 (25.0)
6. Did the review authors perform data extraction in duplicate?	42 (80.8)	NA	10 (19.2)
7. Did the review authors provide a list of excluded studies and justify the exclusions?*	7 (13.5)	1 (1.9)	44 (84.6)
8. Did the review authors describe the included studies in adequate detail?	17 (32.7)	30 (57.7)	5 (9.6)
9. Did the review authors use a satisfactory technique for assessing the RoB in individual studies that were included in the review?*	45 (86.5)	0 (0)	7 (13.5)
10. Did the review authors report on the sources of funding for the studies included in the review?	6 (11.5)	NA	46 (88.5)
11. If meta-analysis was performed did the review authors use appropriate methods for statistical combination of results?*	41 (78.8)	NA	11 (21.2)
12. If meta-analysis was performed, did the review authors assess the potential impact of RoB in individual studies on the results of the meta-analysis or other evidence synthesis?	17 (32.7)	NA	35 (67.3)
13. Did the review authors account for RoB in individual studies when interpreting/discussing the results of the review?*	17 (32.7)	NA	35 (67.3)
14. Did the review authors provide a satisfactory explanation for, and discussion of, any heterogeneity observed in the results of the review?	32 (61.5)	NA	20 (38.5)
15. If they performed quantitative synthesis did the review authors carry out an adequate investigation of publication bias (small study bias) and discuss its likely impact on the results of the review?*	24 (46.2)	NA	26 (53.8)
16. Did the review authors report any potential sources of conflict of interest, including any funding they received for conducting the review?	40 (76.9)	NA	12 (23.1)

AMSTAR 2: A MeaSurement Tool to Assess systematic Reviews 2; NA: Not applicable.

*Critical domain items.

Table 3. Overall methodological quality of the 52 included systematic reviews on atopic dermatitis treatments by bibliographical characteristics.

Bibliographical characteristics	High*	Moderate*	Low*	Critically low*	P
Total included SRs	1 (1.9)	0 (0)	6 (11.5)	45 (86.5)
Cochrane review					0.004*
No	0 (0)	0 (0)	4 (8.7)	42 (91.3)
Yes	1 (16.7)	0 (0)	2 (33.3)	3 (50.0)
An update of a previous SR					0.027*
No	0 (0)	0 (0)	6 (13.3)	39 (86.7)
Yes	1 (14.3)	0 (0)	0 (0)	6 (85.7)
SRs reporting intervention harms					0.627
No	0 (0)	0 (0)	1 (6.7)	14 (93.3)
Yes	1 (2.7)	0 (0)	5 (13.5)	31 (83.8)
SRs that searched non-English databases					0.076
No	1(2.7)	0 (0)	0 (0)	17 (94.4)
Yes	1(2.7)	0 (0)	0 (0)	17 (94.4)
Included a PRISMA-like flow diagram					0.784
No	0 (0)	0 (0)	0 (0)	3 (100)
Yes	1 (2.0)	0 (0)	6 (12.2)	42 (85.7)
Location of corresponding author					0.007*
Europe	1 (8.3)	0 (0)	4 (33.3)	7 (58.3)
America	0 (0)	0 (0)	1 (14.3)	6 (85.7)
Asia	0 (0)	0 (0)	1 (3.2)	30 (96.8)
Oceania	0 (0)	0 (0)	0 (0)	1 (100)
Africa	0 (0)	0 (0)	0 (0)	1 (100)
Funding location of SR					0.002*
Europe	1 (10.0)	0 (0)	4 (40.0)	5 (50.0)
America	0 (0)	0 (0)	1 (25.0)	3 (75.0)
Asia	0 (0)	0 (0)	1 (7.7)	12 (92.3)
Oceania	0 (0)	0 (0)	0 (0)	0 (0)
Africa	0 (0)	0 (0)	0 (0)	1 (100)
Not reported	0 (0)	0 (0)	0 (0)	24 (100)
Type of interventions					0.888
Non-pharmacological	0 (0)	0 (0)	0 (0)	7 (100)
Pharmacological	1 (2.4)	0 (0)	5 (11.9)	36 (85.7)
Both	0 (0)	0 (0)	1 (33.3)	2 (66.7)
Reported year of coverage of literature search					0.925
No	0 (0)	0 (0)	0 (0)	1 (100)
Yes	1 (2.0)	0 (0)	6 (11.7)	44 (86.3)
Search terms reported for one or more electronic databases					0.220
Topics/free text/keywords/MeSHs	0 (0)	0 (0)	0 (0)	26 (100)
Full Boolean	1 (4.2)	0 (0)	6 (25.0)	17 (70.8)
Readers are referred elsewhere for full search strategy	0 (0)	0 (0)	0 (0)	1 (100)
No search term	0 (0)	0 (0)	0 (0)	1 (100)
Language of included primary studies in SR					0.650
English only	0 (0)	0 (0)	3 (13.6)	19 (86.4)
Language other than English	0 (0)	0 (0)	0 (0)	0 (0)
English and languages other than English	1 (3.3)	0 (0)	3 (10.0)	26 (86.7)
Language criteria not reported	0 (0)	0 (0)	0 (0)	0 (0)
Tools for assessing quality of primary studies					0.576
Cochrane risk of bias	1 (2.7)	0 (0)	5 (13.5)	31 (83.8)
Jadad scale	0 (0)	0 (0)	0 (0)	1 (100)
More than one tool	0 (0)	0 (0)	1 (16.7)	5 (83.3)
Not reported	0 (0)	0 (0)	0 (0)	8 (100)

NA: Not applicable; MeSHs: Medical Subject Headings; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-analysis; SR: Systematic review.