Table 2.
Summary of the included studies in the systematic review.
| Source | Population | Recruited or analyzed (n) | Percentage of sex, age (years), or mean (SD) | Experimental intervention | Comparator intervention | Dropout rate (%) | Reason for dropouts (EG/CGa) | Length of intervention (months) |
| Armstrong et al, 2011 [34]; United States | English speakers aged >18 years | EG: 47/43; CG: 47/40; n=94 | Female: 50%; male: 50%; 37.2 years | Online video addressing how sunscreen works to protect skin | Active (brochure) | EG: 8.5% (4/47); CG: 14.9% (7/47) | Lost to follow-up | 3 |
| Böttcher et al, 2019 [35]; Germany | Young organ transplant recipients | EG1: 44/39; EG2: 49/40; CG: 44/33; n=137 | Female: 44.5%; male: 55.5%; 12.6 years | EG1: SMS text message providing sun protection advice; EG2: WBIb with sun protection training | No intervention (waitlist) | EG1: 11.4% (5/44); EG2: 18.4% (9/49); CG: 25.0% (11/44) | N/Rc | 12 |
| Bowen et al, 2019 [36]; United States | First-degree relatives of melanoma cases | EG: 157/141; CG: 156/137; n=313 | Female: 63.6%; male: 36.4%; 51.3 years | WBI with weekly messages of melanoma prevention behaviors | No intervention (waitlist) | EG: 10.2% (16/157); CG: 12.2% (19/156) | Lost to follow-up | 12 |
| Brinker et al, 2020 [37]; Brazil | Secondary school pupils | EG: 734/734; CG: 839/839; n=1573 | Female: 51.6%; male: 48.4%; 15.9 (SD 1.3) years | App that modifies a selfie according to different levels of UV exposure for future 5 to 25 years based on individual skin type | No intervention | EG: 17.3% (127/734); CG: 6.20% (52/839) | Lost to follow-up | 6 |
| Buller et al, 2015 [38]; United States | Adults aged >18 years owning a smartphone | EG: 96/89; CG: 106/104; n=202 | Female: 73.5%; male: 26.5%; 33.3 (SD 9.8) years | App giving feedback on sun protection and alerted users to apply or to reapply sunscreen and to get out of the sun | No intervention | EG: 7.3% (7/96); CG: 1.9% (2/106) | Lost to follow-up and survey not completed | 3 |
| Craciun et al, 2011 [39]; United Kingdom, Germany, Portugal, and Romania | Female volunteers | EG1: 74/74; EG2: 70/70; CG: 61/61; n=205 | Male: 0%; female: 100%; 25.1 (SD 8.7) years | EG1: WBI volitional theory–based; EG2: WBI motivational theory–based | No intervention | 0% | Not applied | 1 |
| Hacker et al, 2018 [40]; Australia | Young adults aged 18-35 years | EG1: 41/35; EG2: 42/36; CG: 41/36; n=124 | Female: 65.8%; male: 31.5%; 25.8 years | EG1: app that displays the daily UV index and gives sun protection advice; EG2: wearable with UV dosimeter | No intervention | EG1: 14.6% (6/41); EG2: 14.3% (6/42); CG: 12.2% (5/41) | Lost to follow-up | 3 |
| Heckman et al, 2016 [41]; United States | Adults aged 18-25 years | EG1: 287/195; EG2: 338/205; CG: 340/229; n=965 | Female: 66.1%; male: 33.9%; 21.8 (SD 2.2) years | EG1: WBI with a tailored intervention based on the Integrative Model of Behavioral Prediction; EG2: WBI with the Skin Cancer Foundation website | No intervention | EG1: 32.1% (92/287); EG2: 39.4% (133/338); CG: 32.7% (111/340) | N/R | 3 |
| Hillhouse at al, 2017 [42]; United States | Female adolescents | EG: 214/182; CG: 229/206; n=443 | Female: 100%; male: 0%; 15.2 (SD 2.0) years | WBI to reduce ITd motivations | Active (placebo) | EG: 15.9% (32/214); CG: 10.1% (23/229) | Lost to follow-up | 6 |
| Manne et al, 2021 [43]; United States | Participants at increased risk for melanoma aged 18-89 years | EG: 56/43; CG: 60/56; n=116 | Female: 69.8%; male: 30.2%; 51.1 (SD 15.2) years | WBI to improve SSEe and sun protection | No intervention | EG: 76.8% (13/56); CG: 93.3% (4/60) | Survey not completed | 3 |
| Marek et al, 2018 [44]; United States | Adults aged ≥18 years | EG1: 18/18; EG2: 17/17; EG3: 17/17; CG: 17/17; n=69 | Female: 61.1%; male: 38.9%; 54.3 (SD 13.9) years | EG1: app allowing total body photography; EG2: SMS to remind SSE; EG3: SMS+ accountability partner | Active (accountability partner) | 0% | Not applied | 6 |
| Reilly et al, 2021 [45]; Scotland | Adults aged >18 years who survived stage 0-2C primary cutaneous melanoma | EG: 121/82; CG: 119/86; n=240 | N/Af | App to encourage and improve SSE | No intervention | EG: 32.2% (39/121); CG: 27.7% (33/119) | Lost to follow-up | 12 |
| Robinson et al, 2016 [46]; United States | Kidney transplant recipients | EG: 84/78; CG: 86/83; n=170 | Female 40.6%; male: 59.4%; 50.0 years | App with educational sun protection content | Active (usual education) | EG: 7.1% (6/84); CG: 3.5% (3/86) | Lost to follow-up | 1.5 |
| Robinson et al, 2021 [47]; United States | Female adults | EG: 494/390; CG: 495/414; n=989 | Female: 100%; male: 0%; 47.0 years | SMS to remind SSE | Active (brochure) | EG: 21.1% (104/494); CG: 16.4% (81/495) | Survey not completed and discontinued intervention (EG) | 3 |
| Stapleton et al, 2015 [48]; United States | Female adults aged 18-25 years with IT in the past 12 months | EG: 94/74; CG: 93/85; n=186 | Female: 100%; male: 0%; 19.8 (SD1.4) years | WBI with psychoeducational content to reduce IT | No intervention | EG: 8.5% (8/94); CG: 8.6% (8/93) | No response | 1.5 |
| Tsai et al, 2017 [49]; United States | Adults aged ≥18 years | EG: 71/42; CG: 72/34; n=143 | Female: 74.1%; male: 25.9%; 42.3 years | Online melanoma video tutorial + brochure | Active (brochure) | EG: 40.8% (29/71); CG: 52.8% (38/72) | Lost to follow-up | 1 |
| Vuong et al, 2018 [50]; Australia | General practice patients | EG: 134/89; CG: 138/96; n=272 | Female: 71.7%; male: 28.3%; 45.5 years | WBI with tailored melanoma risk assessment and prevention + usual education | Active (usual education) | EG: 33.9% (45/134); CG: 30.4% (42/138) | Lost to follow-up | 1.5 |
aCG: comparator group; EG: experimental group.
bWBI: web-based intervention.
cN/R: not reported.
dIT: indoor tanning.
eSSE: skin self-examination.
fN/A: not applicable.