Only 5.04% of hospitals failed to send ICD-9-CM data, but almost half (47.4%) failed to send chief complaints. For example, of the 239,617 sets of cleaned data received in July 2005, about 7.1% of ICD-9-CM information was lacking or filled out as 'null' and 54.82% of cases did not include chief complaints. Additionally, certain hospitals transmitted the patients' chief complaints in Chinese, further complicating the analysis. Because of these difficulties, this report focuses on the data based on ICD-9-CM diagnostic codes only. The time-series plots of the 11 syndrome groups (Figure 4 , 5) that may correlate to infectious diseases and important health problems in Taiwan (e.g., asthma has become an important pediatric problem in recent years) were analyzed.