In health care, not all patients are equal. Some need costly treatment while others are relatively healthy, so providers must often decide who requires more attention and resources. Reston-based information technology firm Altruista Health is attempting to automate that decision process, using its own predictive algorithm to identify a hospital's sickest patients. Mining millions of health records, the 75-person company's software performs a sort of triage, alerting physicians to patients statistically at risk of worsening and then providing treatment suggestions.