Table 2.
Primary outcomes at baseline (T1), after the intervention (T2), and at the follow-up (T3), as well as difference scores (T1 vs T2 and T1 vs T3).
| Outcome per arm | Score at T1, mean (SD) | Score at T2, mean (SD) | Score at T3, mean (SD) | T1 vs T2, mean difference (95% CI) | T1 vs T3, mean difference (95% CI) | |||
| CESD-Ra | –8.09 (–10.13 to –6.05) | –9.79 (–13.26 to –6.33) | ||||||
|
|
Chatbot | 28.33 (13.84) | 20.33 (11.94) | 18.41 (13.44) |
|
|
||
|
|
Control | 30.74 (13.94) | 23.03 (14.30) | 23.00 (14.44) |
|
|
||
| PANASb-Positive | 2.56 (1.30 to 3.81) | 2.51 (1.21 to 3.82) | ||||||
|
|
Chatbot | 17.89 (6.51) | 20.27 (6.29) | 21.22 (5.56) |
|
|
||
|
|
Control | 17.71 (5.52) | 20.66 (7.09) | 20.13 (5.88) |
|
|
||
| PANAS-Negative | –3.83 (–5.39 to –2.27) | –4.38 (–6.26 to –2.50) | ||||||
|
|
Chatbot | 31.19 (7.70) | 27.00 (7.26) | 26.81 (8.81) |
|
|
||
|
|
Control | 32.50 (7.86) | 29.77 (8.76) | 29.16 (8.46) |
|
|
||
| PHQ-9c | –2.56 (–3.44 to –1.69) | –2.82 (–3.91 to –1.72) | ||||||
|
|
Chatbot | 9.97 (4.98) | 7.64 (4.53) | 7.22 (4.56) |
|
|
||
|
|
Control | 11.87 (5.40) | 9.11 (5.59) | 9.50 (5.32) |
|
|
||
| PSWQd | –2.36 (–3.79 to –0.92) | –2.84 (–4.47 to –1.21) | ||||||
|
|
Chatbot | 9.97 (4.98) | 7.64 (4.53) | 7.22 (4.56) |
|
|
||
|
|
Control | 11.87 (5.40) | 9.11 (5.59) | 9.50 (5.32) |
|
|
||
| R-UCLAe | –1.56 (–3.23 to 0.11) | –1.11 (–3.14 to 0.92) | ||||||
|
|
Chatbot | 45.44 (12.15) | 43.06 (13.38) | 41.67 (13.08) |
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|
||
|
|
Control | 42.39 (13.25) | 41.49 (13.42) | 43.69 (12.84) |
|
|
||
| STAIf | –3.31 (–4.61 to –2.01) | –3.40 (–4.99 to –1.80) | ||||||
|
|
Chatbot | 51.86 (8.75) | 48.82 (9.25) | 47.44 (9.78) |
|
|
||
|
|
Control | 52.42 (8.99) | 48.54 (8.94) | 49.53 (7.96) |
|
|
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| SWLSg | 1.44 (0.66 to 2.22) | 1.34 (0.34 to 2.34) | ||||||
|
|
Chatbot | 17.61 (6.67) | 18.97 (7.03) | 20.00 (7.61) |
|
|
||
|
|
Control | 19.50 (5.49) | 20.91 (6.07) | 19.91 (6.00) |
|
|
||
aCESD-R: Center for Epidemiologic Studies Depression Scale Revised.
bPANAS: Positive and Negative Affect Scale.
cPHQ-9: Patient Health Questionnaire-9.
dPSWQ: Penn State Worry Questionnaire.
eR-UCLA: Revised UCLA Loneliness Scale.
fSTAI: State-Trait Anxiety Inventory.
gSWLS: Satisfaction With Life Scale.