General Science

  • verb to make something inaccurate or unbalanced


  • noun the amount by which something is not correctly aligned


  • To distort in some manner, especially in reference to a given desired center, location, position, axis, or instant. For example, clock skew, the distortion resulting from a misaligned head, or that arising from improper horizontal sync.
  • To take or move in a slanted direction. A skewed sheet working its way through a printer, for instance, may result in a jam.
  • A slanting position, movement, or direction. For example, a line which is neither parallel with, nor intersecting with another.

Health Economics

  • (written as Skew)
    A distribution is said to be skewed if it is asymmetrical, having either a long tail to the left (negatively skewed) or a long tail to the right (positively skewed). In a positively skewed distribution, the mean is larger than the median (which is larger than the mode) and vice versa for a negatively skewed distribution. In cost-effectiveness analysis studies, the cost data often display right-skewedness partly because costs cannot be negative and partly because a small fraction of patients often consume a disproportionately large amount of health care resources. In the distribution of income (see figure) most people make under $50 000 a year, but some make lots more and a small number make many millions a year. The positive tail therefore stretches out while the negative tail stops at zero.