Table 6.
Risk of bias and study limitations.
| Study | Risk-of-bias assessment | Risk-of-bias findings | Limitations |
| Tabak et al [8], 2014 | NRa | Moderate risk (selection and attrition biases) | Small sample, high dropout (86% in CGb), and low exercise adherence (21%) |
| Mazzoleni et al [14], 2014 | NR | Moderate risk (small sample size and lack of blinding) | Small sample, short duration, and lack of long-term follow-up |
| Kotrach et al [15], 2015 | NR | Moderate risk (small sample size and preliminary data) | Small sample size, lack of long-term follow-up, and exclusion due to language barriers |
| Hoaas et al [12], 2016 | NR | Moderate risk (small sample size) | Small sample size and seasonal effects on adherence |
| LeGear et al [16], 2016 | NR | Moderate risk (small sample size and short duration) | Small sample size, lack of long-term follow-up, and supervision needed for safe exercise |
| Liu et al [17], 2016 | NR | Moderate risk (lack of randomization and single-site study) | Small sample size, lack of long-term follow-up, monocentric, and limited applicability to patients classified as GOLDc stage 4 |
| Bamidis et al [18], 2017 | Not assessed in early stages of project | Risk of bias expected due to self-reported data and social desirability | No long-term results yet; potential for socioeconomic and geographic disparities in outcomes |
| Burkow et al [19], 2018 | NR | Low generalizability due to small sample size and bias from prior rehabilitation experience | Small sample size, self-reported activity data, and lack of a CG |
| De Las Heras et al [20], 2018 | NR | Moderate risk (small sample size and subjective feedback) | Small sample size and lack of long-term follow-up; only Nordic countries involved |
| Parent et al [21], 2018 | NR | Moderate risk (small sample size; single session) | Short study duration, small sample size, and lack of long-term follow-up |
| Rutkowski et al [22], 2019 | NR | Moderate risk (short intervention duration) | Short duration, lack of long-term follow-up, and no blinding of participants |
| Sutanto et al [23], 2019 | NR | Moderate risk (small sample size) | Small sample size, unblinded study, and lack of intensity monitoring for the Wii exercises |
| Jung et al [13], 2020 | NR | Moderate risk (small sample size and acknowledged limitations) | Small sample size and limited generalizability |
| Rutkowski et al [11], 2020 | NR | Low risk (structured randomization and CG) | Short duration (2 wk); only patients classified as GOLD stages 2 and 3 included |
| Tu et al [24], 2020 | NR (demonstration phase) | NR | Small-scale demonstration, short duration, and lack of long-term data |
| Rutkowski et al [9], 2021 | Assessor-blinded RCTd with controlled randomization (low risk of bias) | Low risk (structured randomization and CG) | Short duration; only hospital based |
| Simmich et al [25], 2021 | NR | Low risk (small sample size and self-reported data) | Lack of generalizability due to the small sample size and limited geographic representation |
| Simmich et al [26], 2021 | NR | Possible bias due to the involvement of the EGe in co-design | Small sample size, short trial duration, Fitbit issues, and lack of notifications in the game |
| Baxter et al [27], 2022 | NR | Low risk (randomization and crossover design) | Small sample, short session duration, and lack of clinical participants |
| Oberschmidt et al [28], 2022 | NR | Some dropouts due to exacerbation but not directly related to intervention | Small sample size, dropouts after 12 wk, and occasional technical issues |
| Finkelstein et al [29], 2023 | NR | Low risk (all participants completed the tasks without significant issues) | Small sample size; lack of long-term follow-up |
| Gabriel et al [30], 2023 | NR | Low risk (comprehensive task completion by all participants) | Small sample size, no CG, and lack of long-term follow-up |
| Gabriel et al [31], 2023 | NR | Low risk (most participants completed the tasks easily) | Small sample size, short duration, and lack of long-term follow-up |
| Pancini et al [32], 2023 | NR (planned study) | NR (study pending implementation) | Small sample size; short intervention duration |
| Pardos et al [33], 2023 | NR (pilot) | NR | Exclusion of factors such as nutrition, smoking, and drinking; system still in development |
| Colombo et al [34], 2024 | NR | Low risk (high adherence and positive outcomes) | Small sample size; no CG |
| Jin et al [35], 2024 | NR | Low risk (group similarity and controlled environment) | Lack of long-term adherence tracking; reliance on self-report |
| Kizmaz et al [36], 2024 | NR | Likely low risk, given the blinded evaluator and randomized design | No objective assessment of cybersickness or patient satisfaction; no third group for comparison with usual care |
| McAnirlin et al [10], 2024 | NR | NR | Small sample size, no CG, and exploratory design |
aNR: not reported.
bCG: control group.
cGOLD: Global Initiative for Chronic Obstructive Lung Disease.
dRCT: randomized controlled trial.
eEG: experimental group.