It has been observed during the course of our 15 years of experience in the data entry business that clients follow the single data entry method for their offline and, specially for, online data entry.
While the accuracy for the single entry method can go as high as 99%, but is usually lower. This accuracy may suffice for statistical data like surveys, it would not in most other cases. There is no cross checking the data entered by an operator.
As far as accuracy goes the “double entry” method, also called “dual entry”, is proven to be the most accurate (Kawado et al., 2003; Reynolds-Haertle & McBride, 1992). Accuracy can be as high as 99.99%. Many studies have been made by researchers, on this subject, and can be found on the net. (copy/paste URL to google.com faculty.unlv.edu/barchard/doubleentry/Double-Entry-APS-2009-handout.pdf).
Online data entry
A lot of the data entry work is outsourced to vendors for entry into client-end servers. The process uses high bandwidth internet at the vendor end. At the client-end there is a web based form which displays the images and the data entry fields. Data is keyed off each image remotely by the operator and stored in a database residing in the client-end server. While this is a secure process since no images or data is downloaded to vendor network, the accuracy of the data falls short of expectations.
The web based form in the client-end server could be designed to support “double entry”. In “double entry” the same set of images are entered by two different operators. The client-end web based software could be built on the .Net platform with MS Access in the backend.
In the “double entry” method, during the second entry, known as “verification”, the software matches the data entered, on a character level, with the data from the “first entry”. The software displays both versions where ever there is a mismatch between what has been previously entered and is being entered now. The operator would have to make a selection of one version, after verifying with the image. Unless the operator clears a mismatch the system would not allow the operator to proceed further.
The “double entry” method is a proven process for achieving very high accuracies and should be followed even for online data entry. The only lacuna is designing the software which supports “double entry”. Normally developers are not aware of the requirement so have not worked on this aspect.
We could develop an online data entry system which supports “double entry” for a client. The system would pay-off if the volumes are high and data entry perpetual in nature or for a fairly long period.
CyberData India is an information management company, with fifteen years of experience in the India data entry, image editing, indexing, OCR cleanup business which give us an edge over others. Our quality control processes are ISO 9001: 2008 certified. For more information visit us at http://www.edatashop.com.