1. A computer system comprising: a data storage module for receiving, storing, and providing access to claim data, the claim data representing historical and current long term disability claims; a proactive referral model component, coupled to the data storage module, for determining whether to identify a one of said current claims for referral to an investigation unit, said proactive referral model based on a plurality of variables, the variables including at least one of: (a) a variable that indicates that a claimant's diagnosis has changed; (b) a variable that indicates that the one of said current claims was brought under any-occupation coverage; (c) a variable that reflects a market segment for a policy under which the one of said current claims was brought; (d) a variable that has a value based on a state in which the claimant resides; and (e) a variable that represents an amount of experience of a claims handler who handled the one of said current claims; a computer processor for executing programmed instructions and for storing and retrieving said data related to current claims; program memory, coupled to the computer processor, for storing program instruction steps for execution by the computer processor; a model training component, coupled to the computer processor, for training the proactive referral model component based on the data related to the historical claims in accordance with program instructions stored in the program memory and executed by the computer processor, thereby providing a trained proactive referral model component; an output device, coupled to the computer processor, for outputting an output indicative of whether said one of said current claims should be referred to the investigation unit, wherein the computer processor generates the output in accordance with program instructions in the program memory and executed by the computer processor, said output generated in response to application of data for said one of said current claims to the trained proactive referral model component; and a routing module for directing workflow based on the output from the output device.