Manufacturer changes lead to clinically important differences between two editions of the TNO stereotest

Abstract

This is the accepted version of the paper.This version of the publication may differ from the final published version. Abstract Purpose: Stereoacuity tests used in clinical practice should be repeatable and reproducible. However, it has been observed in a clinical setting that new editions of the TNO stereotest appear to give different values from those obtained using previous versions. The purpose of the present research was to investigate this observation. Methods: One hundred and twenty-one Dutch subjects, 88 (73%) females and 33 (27%) males, with an average age of 34.0 years (range 18-55) had their stereoacuity measured using two different versions of the TNO stereoacuity test (TNO 13 and TNO 15). The TNO was tested in a counterbalanced order so that consecutive subjects started with alternate editions to avoid bias. Results: There was a significant difference (p < 0.001) between the median value for stereoacuity measured with TNO 13 (30 s of arc) and TNO 15 (60 s of arc). The bias between the two test versions was À0.23 Log arcseconds (95% limits of the differences: 0.15 to À0.60 Log arcseconds). Conclusion: This study reveals that results obtained with two different editions of a commonplace stereoacuity test are not comparable. New versions come on the market at regular intervals and the assumption that they will give the same results as previous versions may not be valid. Besides the statistically significant difference between the TNO 13 and TNO 15, the Bland-Altman plot also showed a considerable bias and the 95% limits of the differences between the TNO 13 and TNO 15 are more than two steps on the Log arcsecond scale. This difference between two editions of the TNO stereotests is not clinically acceptable and therefore it is inappropriate to use the two versions of the test interchangeably. It is important in both research and clinical records to specify the edition of the TNO test used. Permanent repository link

Overestimation of stereo thresholds by the TNO stereotest is not due to global stereopsis

“…29,36 Average differences of 30 arcsec between various editions of the TNO have been reported before and have been related to differences in the printing process, however this has not yet been investigated for the 9th and 10th edition of the test that were used in our study. 37 Our results are also in congruence with a study by Gadia and colleagues who showed correspondence between stereo thresholds of Randot Circles and a software-based stereo acuity test. 38 The similar thresholds obtained with our local clinical, local psychophysical and global psychophysical stereotests indicate that the higher thresholds obtained with TNO, a clinical test for global stereopsis, cannot be attributed to increased difficulty of global stereopsis compared to local stereopsis, as has been suggested before.…”

Estudio de la eficacia del test TNO en la detección precoz de la ambliopía en atención primaria

“…El éxito del tratamiento depende de una detección y de un tratamiento precoz durante la infancia. (1)(2)(3)(4)(5) Se considera de primordial importancia la detección temprana de las alteraciones visuales causales de la ambliopía, ya que su tratamiento es sólo efectivo durante la maduración del sistema visual en la infancia, evitando de esta forma las negativas consecuencias de una visión inadecuada en la etapa adulta.…”

Reliability of near stereoacuity tests: Titmus, Randot, TNO, and Frisby

“…El test TNO parece ser el más riguroso con un valor normal de 60" y un rango que va desde 15" a 240" [4] o 49±26.3" [3] pero nuestros resultados muestran que sólo el 75% de la población estudiada, independientemente del género, alcanza 60". A pesar de esto, se ha descrito que el nivel de estereoagudeza depende de la edición del test realizado [12]. Independientemente de esta variación, van Doorn et al [12] describió valores medios desde 30" a 60" coincidiendo con Rosner and Clift (n=20) y con Heron et al (n=51) [13,14] pero nuestros cortes de normalidad del 85% y del 95% establecen que los sujetos pueden alcanzar aproximadamente 120" y 240" respectivamente.…”

“…A pesar de esto, se ha descrito que el nivel de estereoagudeza depende de la edición del test realizado [12]. Independientemente de esta variación, van Doorn et al [12] describió valores medios desde 30" a 60" coincidiendo con Rosner and Clift (n=20) y con Heron et al (n=51) [13,14] pero nuestros cortes de normalidad del 85% y del 95% establecen que los sujetos pueden alcanzar aproximadamente 120" y 240" respectivamente. En relación al test de Titmus, el valor medio de 40", rango 40"-60", [4] y de 41±3" [3] se han descrito previamente pero estos valores tan restrictivos están lejos de los que nosotros hemos encontrado en este estudio.…”