Factors associated with underreporting of adverse drug reactions by patients: a systematic review

Table 2 Studies that assessed the sociodemographic characteristics and reasons associated with underreporting adverse drug reactions

Author (Year of publication)	Sociodemographic characteristics^b	Reasons for under-reporting adverse drug reactions^c
Author (Year of publication)	Sociodemographic characteristics^b	Complacency	Ignorance	Lethargy	Others
Wang et al. (2022) [37]		NR	72.58%	16.49%	10.71%
Januskiene et al. (2021)^a [38]		NR	23.99%	3.69%	✔
Pillay et al. (2021) [39]		NR	37.38%	17.00%	✔
Al Dweik et al. (2020) [40]		✔	✔	NR	✔
Kim et al. (2020) [41]	Sex, monthly income	NR	71.30%	NR	63.50%
Adisa and Omitogun (2019)^a [42]	Age	14.70%	27.40%	NR	NR
Adisa et al. (2019) [43]		NR	NR	NR	15.40%
Jacobs et al. (2019) [44]	Age, region	NR	✔	NR	✔
Sabblah et al. (2017) [45]	Age, sex, level of education, profession/employment status	14.80%	10.80%		37.00%
Patsuree et al. (2016) [46]		NR	70.40%	17.10%	42.90%
Matos et al. (2015) [47]	Level of education	24.60%	NR	NR	NR
Robertson and Newby (2013) [48]		35.60%	NR	16.40%	26.40%
Fortnum et al. (2012) [49]	Social grade, level of education	22.00%	16.20%	7.40%	14.80%

✔—In studies where the reasons were stated but whose numerical measures were not mentioned, the symbol ✔ was used
NR Not reported
^aArticle with information on HCPs and patients, however only patient information was retrieved
^bSociodemographic characteristics reported to be statistically significantly associated with ADR reporting
^cThe total numerical percentage regarding each reason for underreporting ADRs within each study was either extracted directly from the study (one specific question for each reason) or calculated using the mean/median (i.e. when more than one question within the same study was associated to a certain reason)