Tactile/kinesthetic stimulation effects on preterm neonates.

To the Editor.— The provocative study by Field et al (Pediatrics 1986;77:654-658) attributes a 47% increase in rate of weight gain to tactile/kinesthetic stimulation of preterm infants, but the reader is presented with a number of perplexing problems in interpretation. We are unable to understand the randomization process, which was achieved after a stratification exercise designed to divide patients into eight poststratification groups. If these were equal in size, then each group must have contained five patients, an odd number.