Patient characteristics
Study populations included adults 18 to 82 years. Almost all studies include both female and male participants. Several types of cancers were accepted for participation, for instance, four studies included all types of cancers. The most prevalent type was head and neck cancer in 11 studies(Planting et al., 1999, Madasu et al., 1995, Ishikawa et al. 2015, Duinkerken et al., 2021, Zuur et al., 2007, Rolland et al., 2019, Yoo et al., 2014, Riga et al. 2013, Crabb et al., 2017, Fernandez et al., 2021, Campbell et al. 2022). Other types were ovarian, bladder, germ cell, gastric, lung, breast, sarcoma, thymus, mesothelioma, esophagus, melanoma, and cancer of unknown origin. Most of the studies recruited patients about to begin chemotherapy, with no prior history of auditory surgery, affection, or disease, and good performance status. Cisplatin dose ranged between 75 to 517 milligrams per square meter (mg/m2), an average of 138 mg/m2. Study exclusion criteria varied, with some studies excluding patients with metastasis in the central nervous system, hepatic or renal insufficiency, hearing asymmetry, hearing aid users, and concomitant neuropathy or radiotherapy. In regards to this last condition, there was great heterogeneity between studies, 10 studies demanded or allowed concomitant radiotherapy (Planting et al., 1999, Madasu et al., 1995, Ishikawa et al. 2015, Duinkerken et al., 2021, Zuur et al., 2007, Rolland et al., 2019, Yoo et al., 2014, Fernandez et al., 2021, Scasso et al. 2017, Campbell et al. 2022) while 13 considered radiotherapy as an exclusion criterion. For those studies that reported follow-up time, the mean was 6,4 months.