Background: Effective and efficient health care services need evidence-based decisions and theserndecisions should rely on information from high-quality data. However, despite a lot of efforts, routinernhealth data is still claimed to be not at the required level of quality for decision-makers. Previous studiesrnhave primely relay on organization-related factors little emphasis was given for perception andrnknowledge of service providers' gaps. Therefore, this study aims to evaluate the quality of data generatedrnfrom routine health information systems and factors contributing to data quality from diverse aspects. rnObjective: To assess the quality of data from routine health information systems and factors contributingrnto data quality collected in health centers of Addis Ababa City administration, Ethiopia. rnMethod: A cross-sectional study was conducted on 568 health professionals from 33 health centersrnselected randomly using a two-stage sampling method. A qualitative study was conducted using 12 keyrninformants. The World Health Organization data quality report card framework and PRISM tools are usedrnto assess the quality of routine health data and factors affecting it. Descriptive statistics, correlation,rnANOVA, and non-parametric tests were done using SPSS version 23. Qualitative data analysis was donernusing ATLAS ti version 7.5 using a thematic analysis approach. rnResult: Timeliness of report, data accuracy, registration completeness, and report completeness level ofrnthe selected facilities was 40.39%, 76.67%, 96%, and 93.93%, respectively. The overall regional datarnquality level was 76.22%. Health professional perception on evidence-based decision making, thernemphasis given to data quality, feedback, and health professionals motivation towards routine health carerndata have shown a strong association with data quality,(r (31) =.78, p