Letters to the Editor

Indian Pediatrics 2002; 39:401-402  

Effects of Tactile-Kinesthetic Stimulation in Preterms

The recent article(1) on this subject needs some clarification. The authors systematically allocated their patients based on the starting date of the week, but systematic allocation of subjects is no substitute for randomization. If the authors were concerned that control group mothers would have dropped out, they should have resorted to a cluster randomization method to minimize selection bias. The authors have not specified whether any special measures were taken to ensure that the mothers in the 2 groups received identidical counseling regarding all aspects of neonatal care except that related to the massage. In an open trial there is always a danger that the test group would receive more attention and counselling from nurses and other staff, thus confounding the results. In this study there was ample scope for blinding the investigator who was doing the follow up anthropometry and the Neonatal Behavioral Assessment, to minimize the measurement bias, but this was not done.

I have serious objections to the choice of the primary outcome variable. The authors have selected as the primary outcome a change in physiological parameters in the period before and after massage on the first 5 days. Firstly, if the main aim of the study was to look at the beneficial effects of this intervention, then the rate of growth or the neurobehavioral assessment at 42 weeks post-menstrual age would have been better primary outcome measures. The change in physiological parameters during the massage is at best a potential adverse effect of the massage and hence should be a secondary outcome. Secondly, the difference in temperature maintenance (a primary outcome) was tested only in the highly controlled hospital environment of 32-34ºC. What was the guarantee that body temperature would have been adequately maintained at home during the period of exposure for the massage? Hypothermia at home is a major concern. Thirdly, what differences were the authors expecting to see between the 2 groups in relation to the primary outcome variable and how did they calculate the sample size based on these expected differences?

From which day was the rate of weight gain calculated–from day 1 of life, or from the day that the baby started gaining weight after reaching a nadir, or from the day that birth weight was regained? This is important because babies in the 1000-2000 g group may take up to 15 days to physiologically regain birth weight. The authors mention in the Methods that 23 babies were recruited in the control group, but Table 1 shows 25 patients in the control group. When were these 2 extra patients recruited?

The authors have not mentioned the degree of compliance in both groups - how many in the test group had stopped the massage and how many in the control group started massaging at home on extraneous advice? The kind of milk used for feeding after discharge and any concurrent infections has also not been mentioned. These could alter the interpretation of the results.

Sourabh Dutta,
Assistant Professor,
Department of Pediatrics,
Post graduate Institute of Medical Education and Research,
Chandigarh 160 012,
India.

1. Mathai S, Fernandez A, Mondkar J, Kanbur W. Effects of tactile-kinesthetic stimulation in preterms: A controlled trial. Indian Pediatr 2001; 38: 1091-1098.