A "recovery" algorithm was developed by Rebane and Pearl (1987) which rests on Wrights distinction between the three possible types of causal substructures allowed in a directed acyclic graph (DAG):

  
    
      
        X
        →
        Y
        →
        Z
      
    
    {\displaystyle X\rightarrow Y\rightarrow Z}
  

  
    
      
        X
        ←
        Y
        →
        Z
      
    
    {\displaystyle X\leftarrow Y\rightarrow Z}
  

  
    
      
        X
        →
        Y
        ←
        Z
      
    
    {\displaystyle X\rightarrow Y\leftarrow Z}
  Type 1 and type 2 represent the same statistical dependencies (i.e., 
  
    
      
        X
      
    
    {\displaystyle X}
   and 
  
    
      
        Z
      
    
    {\displaystyle Z}
   are independent given 
  
    
      
        Y
      
    
    {\displaystyle Y}
  ) and are, therefore, indistinguishable within purely cross-sectional data.
Veterinary medicine
Ketoprofen is a common NSAID, antipyretic, and analgesic used in horses and other equines. It is most commonly used for musculoskeletal pain, joint problems, and soft tissue injury, as well as laminitis. It is also used to control fevers and prevent endotoxemia. It is also used as a mild painkiller in smaller animals, generally following surgical procedures. In horses, it is given at a dose of 2.2 mg/kg/day. Studies have shown that it does not inhibit 5-lipoxygenase and leukotriene B4, as originally claimed. It is therefore not considered superior to phenylbutazone as previously believed, although clinical signs of lameness are reduced with its use. In fact, phenylbutazone was shown superior to ketoprofen in cases of experimentally-induced synovitis when both drugs were used at labeled dosages. Administration
Ketoprofen, when administered intravenously, is recommended for a maximum of five days of use. Its analgesic and antipyretic effects begin to occur one to two hours following administration. The most common dosage is 1 mg/ lb, once per day, although this dosage may be lowered for ponies, which are most susceptible to NSAID side effects. It is also available as a capsule dosage form and tablet. Ecological problems
Experiments have found ketoprofen, like diclofenac, is a veterinary drug causing lethal effects in red-headed vultures. Vultures feeding on the carcasses of recently treated livestock develop acute kidney failure within days of exposure. References
External links

"Ketoprofen". Drug Information Portal. U.S. National Library of Medicine.