Accuracy of smartphone recordings (Barsties v. Latoszek et al., 2025)

<p dir="ltr"><b>Objective: </b>Clinical voice quality assessments typically use external microphones meeting technical standards for instrumental assessment of voice. As smartphones advance, this study aimed to determine their suitability for voice recordings through a systematic review with meta-analysis.</p><p dir="ltr"><b>Method: </b>Three database searches were conducted, ranging from their inception to December 2024, as well as a manual search. Cross-sectional studies were included on widely used clinical acoustic voice quality measures of the software Praat (i.e., jitter, shimmer, harmonics-to-noise ratio [HNR], smoothed cepstral peak prominence [CPPS], and acoustic voice quality index [AVQI]).</p><p dir="ltr"><b>Results:</b> We found 10 eligible research studies with a total of 379 participants who were simultaneously compared between a clinical recording system (CRS) and different smartphones by Apple and Samsung products. All included studies focused on individuals with vocally healthy voices, while four of the studies also included those with voice disorders. In comparison with CRS, iPhones revealed significant differences and large effect sizes in HNR (mean difference of 2.20, 95% CI [0.59, 3.82], <i>p</i> = .008, Cohen’s <i>d</i> = 2.54) and in AVQI (mean difference of −0.53, 95% CI [−1.00, −0.06], <i>p</i> = .027, Cohen’s <i>d</i> = −1.99), but in the direct comparison between Apple and Samsung mobile device recordings, significant differences and large effect sizes were found in jitter (mean difference of −0.17, 95% CI −0.27, −0.08, <i>p</i> < .001, Cohen’s <i>d</i> = −1.18) and CPPS (mean difference of 0.87, 95% CI [0.20, 1.53], <i>p</i> = .011, Cohen’s <i>d</i> = 1.26). Recordings with Samsung products showed only significant differences and a large effect size with CRS in jitter (mean difference of −0.16, 95% CI [−0.29, −0.03], <i>p</i> = .019, Cohen’s <i>d</i> = −0.84).</p><p dir="ltr"><b>Conclusions:</b> The present meta-analysis indicated some inconsistency in the outcomes of acoustic voice quality parameters between smartphone recordings and CRS. While acoustic measurements are frequently used in clinical voice assessments and smartphones are widely available, it is important to note that for certain parameters, current smartphone recordings may not yet match the precision of CRSs for voice quality analyses.</p><p dir="ltr"><b>Supplemental Material S1.</b> Study quality appraisal analyzed with NHLBI Quality Assessment Tool for Observational Cohort and Cross‐Sectional Studies.</p><p dir="ltr">Barsties v. Latoszek, B., Lammertz, C. Z., Awan, S. N., Binkofski, F., Hetjens, S. (2025). The accuracy of smartphone recordings for clinical voice diagnostics in acoustic voice quality assessments: A systematic review and meta‐analysis. <i>American Journal of Speech-Language Pathology,</i><i> </i><i>34</i>(6), 3531–3548. <a href="https://doi.org/10.1044/2025_AJSLP‐25‐00140" rel="noreferrer" target="_blank">https://doi.org/10.1044/2025_AJSLP‐25‐00140</a></p>