A fundamental challenge in making the information gathered from surgeon's certificates available for public use was the development of adequate data collection instruments, or disease screens. The collection screens are the result of extensive analysis of the original surgeons' certificates, led by the medical experts on the research team of the Early Indicators (EI) project. The screens were designed to give some basic structure to the data while still allowing later modifications as more experience was amassed in the collection process. They constitute the format used by the data inputters, and also provide an initial classification scheme that organized the data for further standardization and classification.

The structure of the disease screens is motivated by three primary factors. First, the data are grouped, where possible, according to physiological systems. For example, there are individual screens for the cardiovascular, respiratory, genito-urinary, and gastro-intestinal systems. Variables are named in a way that identifies to which system (collection screen) they belong. For instance, variables such as c_murmur and c_enlarg are identified as cardiovascular variables because of the prefix "c_" that precedes the variables.

Second, the form of the certificates themselves dictate the design of the screens. Examining physicians tended to group their observations according to disease systems. Some of these, such as cardiovascular and genito-urinary, are consistent with modern classification. Other groupings used by the physicians, however, were determined by the specific purpose of the examination, namely, to identify what were considered to be disabling conditions. Therefore, there were individual screens for diarrhea, hernias, hemorrhoids, rheumatism, and varicose veins. Organizing the screens according to the groupings typically used by the examining physicians considerably simplified the collection process.

Finally, the grouping of different conditions is highly correlated with the disability ratings given to conditions. In general, the disease screens represented the level of detail that was commonly found in the ratings. For instance, ratings were usually given for the cardiovascular system as a whole without differentiating between different cardiovascular conditions even though additional detail was often provided about the cardiovascular system. The physicians typically stated something like "$8 for disease of heart". On the other hand, conditions such as hernias, chronic diarrhea, or varicose veins were given individual disease ratings. On each disease screen there is a field for the data inputter to enter the disability rating for that disease screen. Sometimes diseases from different screens are grouped together under a single rating amount, at other times the only rating information provided is a single disability rating that gave the overall amount the physicians recommended the applicant receive.

The following table provides a listing of the disease screens, each with its respective variable group number (VG #) and identifying character. The screens are still being revised and updated, under the supervision of Dr. Louis Nguyen of Brigham and Women's Hospital at Harvard University in Boston.