Misleading title, over-interpretation of findings, other issues
Stephen Gilliver, Lund University / Region Skåne
25 June 2013
This paper by Saetung et al. [1], which describes a crossover trial of the effects of Thai massage on biomarkers of bone formation in postmenopausal women, has a number of flaws. Its title, `Thai massage increases biochemical markers of bone formation: a randomized crossover trial,¿ is misleading as Thai massage only showed an effect on one of the tested biomarkers, P1NP. The other biomarkers tested, CTX and osteocalcin, showed no changes in response to Thai massage. Furthermore, whether the observed 7% increase in serum P1NP level is clinically relevant is questionable, especially when one considers that the within-subject coefficient of variation in serum P1NP levels was found in one study [2] to be approximately 12% in a group of postmenopausal women.
Despite only showing an effect on one of the three biomarkers tested, the authors conclude that Thai massage increases bone formation. This conclusion is not substantiated by their data. One wonders why the authors did not present data for bone mineral density (BMD) or bone mass, having measured body composition and BMD in different parts of the skeleton by dual-energy X-ray absorptiometry (DEXA). What did the DEXA data show (apart from the rate of osteoporosis)?
While acknowledging that bone and fat mass may affect the response to Thai massage, the authors did not determine whether these factors were associated with the observed change in P1NP level following Thai massage. Moreover, if the authors feel that leptin and ghrelin may be involved in the response to Thai massage, why did they not measure them? They instead measured insulin levels, with no obvious rationale and without presenting the results.
The CONSORT 2010 flow diagram shows that 20 randomized subjects (28%) did not receive the allocated treatment because of `unwillingness to participate.¿ This is surprising. Were prospective participants not informed about the study prior to randomization?
The study by Saetung et al. raises more questions than it answers.
1. Saetung S, Chailurkit LO, Ongphiphadhanakul B: Thai traditional massage increases biochemical markers of bone formation in postmenopausal women: a randomized crossover trial. BMC Complement Altern Med 2013, 13:69.
2. Scariano JK, Garry PJ, Montoya GD, Wilson JM, Baumgartner RN: Critical differences in the serial measurement of three biochemical markers of bone turnover in the sera of pre- and postmenopausal women. Clin Biochem 2001, 34(8):639-644.
Misleading title, over-interpretation of findings, other issues
25 June 2013
This paper by Saetung et al. [1], which describes a crossover trial of the effects of Thai massage on biomarkers of bone formation in postmenopausal women, has a number of flaws. Its title, `Thai massage increases biochemical markers of bone formation: a randomized crossover trial,¿ is misleading as Thai massage only showed an effect on one of the tested biomarkers, P1NP. The other biomarkers tested, CTX and osteocalcin, showed no changes in response to Thai massage. Furthermore, whether the observed 7% increase in serum P1NP level is clinically relevant is questionable, especially when one considers that the within-subject coefficient of variation in serum P1NP levels was found in one study [2] to be approximately 12% in a group of postmenopausal women.
Despite only showing an effect on one of the three biomarkers tested, the authors conclude that Thai massage increases bone formation. This conclusion is not substantiated by their data. One wonders why the authors did not present data for bone mineral density (BMD) or bone mass, having measured body composition and BMD in different parts of the skeleton by dual-energy X-ray absorptiometry (DEXA). What did the DEXA data show (apart from the rate of osteoporosis)?
While acknowledging that bone and fat mass may affect the response to Thai massage, the authors did not determine whether these factors were associated with the observed change in P1NP level following Thai massage. Moreover, if the authors feel that leptin and ghrelin may be involved in the response to Thai massage, why did they not measure them? They instead measured insulin levels, with no obvious rationale and without presenting the results.
The CONSORT 2010 flow diagram shows that 20 randomized subjects (28%) did not receive the allocated treatment because of `unwillingness to participate.¿ This is surprising. Were prospective participants not informed about the study prior to randomization?
The study by Saetung et al. raises more questions than it answers.
1. Saetung S, Chailurkit LO, Ongphiphadhanakul B: Thai traditional massage increases biochemical markers of bone formation in postmenopausal women: a randomized crossover trial. BMC Complement Altern Med 2013, 13:69.
2. Scariano JK, Garry PJ, Montoya GD, Wilson JM, Baumgartner RN: Critical differences in the serial measurement of three biochemical markers of bone turnover in the sera of pre- and postmenopausal women. Clin Biochem 2001, 34(8):639-644.
Competing interests
None