Is the red-yellow-black scheme suitable to classify donor site wounds? An inter-observer analysis.

Abstract

The red-yellow-black-scheme (RYB) is a well-known and validated scheme to classify chronic and acute wounds, based on wound color and moistness. We investigated whether this RYB-scheme is also useful to classify donor site wounds uniformly (DSW). Twenty-three digital photographs of DSWs in various stages of wound healing were presented to internationally renowned wound scientists (n=11), surgical doctors (n=31), specialized wound nurses (n=55), and surgical nurses (n=28). These observers classified the color and moistness of the wound according to the RYB-scheme, yielding seven wound categories. Inter-observer agreement (IOA) was expressed as a kappa (κ) value. IOA's among specialized wound nurses were moderate when based on wound color and moistness (κ=0.41; 95% CI 0.33-0.49), wound color only (κ=0.41; 95% CI 0.29-0.53), or moistness only (κ=0.54; 95% CI 0.45-0.64). However, these IOA's tended to be better than those among the scientists, doctors and nurses. Scientists showed the lowest agreement (k-values between 0.17 and 0.25). Doctors scored slightly better than nurses. Clinicians and scientists have difficulty with classifying DSWs by means of the RYB-scheme. Therefore, this scheme does not appear useful to classify donor site wounds in a uniform manner.