本研究之目的在於探討網路問卷與傳統問卷所收集的資料，是否具有均等的心理計量特性。本研究以流行病學中心憂鬱量表為研究工具，臺灣地區中小學教師為研究對象，經由分層隨機抽樣，分別在高中 (職)、國中、國小，共計抽取2400位教師為樣本，並隨機分派其中的1200人為紙筆組，以郵寄的方式施以傳統問卷調查；另外1200人為網路組，郵寄邀請函邀請其上網填答問卷。本研究藉由結構方程式之多樣本均等性方法學，探討網路問卷 (網路組) 與傳統問卷 (紙筆組) 所得到的資料是否具有均等的心理計量特性。 研究結果顯示，網路問卷與傳統問卷兩組樣本之因棄結構均等性獲得支持；亦即，網路組與紙筆組在憂鬱量表上具有均等的因素負荷量、潛在因素共變數矩陣、測量誤差。在四個潛在因素 (憂鬱情緒、正向情感、身體症狀、人際問題) 的潛在平均數方面，兩組受試者在憂鬱情緒、正向情感、人際問題上無顯著差異，但在身體症狀上差異達顯著 (p<.01)，但是平均數的差異只有0.19分。因此本研究除了統計顯著性檢定之外，進一步以效果量來比較兩組差異的大小，研究結果指出身體症狀之Cohen's d 統計量為.172，顯示兩組的平均數的效果量低。兩組在身體症狀的差異應該是由於樣本數龐大，而造成統計上顯著性的結果，在實務上未達實質意義的差距。 綜上所述，網路組與紙筆組因素結構均等性獲得支持，顯示出兩組在憂鬱量表中的各題，具有均等的因素架構與測量效果，並具有均等的信度與效度，可見此測量工具在不同樣本獲得交叉驗證的支持，再加上極為接近的潛在平均數，均提供網路問卷是傳統問卷可行替代方案的有力証據。因此，本研究認為網路問卷與傳統問卷所得到的資料具有相同的心理計量特性，網路問卷是傳統問卷的可行替代方案。

This study examines whether Internet questionnaires are as psychometrically invariant as traditional mailed questionnaires. A random sample of 2400 teachers in Taiwan was divided into experimental and control groups. The experimental group was asked to complete the electronic version of the CES-D (Center for Epidemiologic Studies Depression Scale) placed on the internet, whereas the control group was invited to complete the traditional paper-based CES-D. The multi-sample invariance approach derived from structural equation modeling (SEM) was applied to analyze the collected data. The analytical results show that the two groups have equivalent factor structures. That is, the two groups exhibit equal factor loadings, covariance matrix for latent factors and measurement errors. The results also show that the items in CES-D function equivalently in the two groups. That is, the instrument exhibits equal validity and reliability when administrated to the two groups. Moreover, the cross validation was also approved by the results. These findings demonstrate that the In­ternet questionnaires and traditional mailed questionnaires had equal factor structures. Given that the factor structures were found to be equivalent, the equal latent mean test was then performed. The analytical results demonstrate that the four latent means in CES­D are not totally equal between two groups. Concerning the four latent factors in CES-D, the latent means of "depressed mood", "positive affect" and "interpersonal problems" are not significantly different between these two groups. However, the difference between the "somatic symptoms" latent means of these two groups is statistically significant at α= .01. To investigate the effect size of such difference, Cohen d statistics was utilized. However, Cohen d statistics was only .172, indicating a small effect size. That is, the minor difference in somatic symptoms, 0.19 point, albeit statistically significant, does not apparently lead to meaningful clinical significances (effect size) in practice. Analytical results indicate that Internet questionnaires and traditional mailed questionnaires have equal factor structures to. Both CES-D questionnaires exhibit equal reliabi­lity, validity and factor structure, and similar latent means. In conclusion, internet questionnaires represent a promising alternative to traditional paper-based questionnaires.