1.1 Subjects
This cross-sectional study was carried out with a total of 400 children of both genders aged (28.14 ± 7.23 months) between 12 and 48 months (F = 203, 28.35 ± 7.99 months; M = 197, 29.14 ± 7.73 months). All these children live in the urban environment of Portugal. For a better analysis and understanding of the results, the participants were divided into three groups by age group: from 12 to 23 months (N = 104, age = 17.79 ± 3.33 months), from 24 to 35 months (N = 152, age = 28.27 ± 3.65 months) and from 36 to 48 months (N = 144, age = 17.35 ± 4.16 months).
These children were grouped as follows: children with guided physical activity (N= 190, age = 33.96 ± 6.99 months); children without oriented physical activity (N= 215, age = 25.83 ± 8.54 months). The guided physical activity classes/activities are 30 minutes long and 2 times a week, and the respective motor skills are worked on depending on the age level.
Initially, a contact was established with institutions, day care centers and/or kindergarten, with which the Institute Polytechnic of Castelo Branco have collaboration protocols, for the possibility of applying the instrument to children.
The following exclusion criteria were considered: Children who have been diagnosed with learning difficulties and/or developmental impairments; Children with some type of diagnosed disability; Children under 12 months and over 48 months.institutions.
1.2 Instruments
The instrument used to collect information on the motor skills of the children under study was the Peabody Developmental Motor Scales - Second Edition (PDMS-2)[14]. The PDMS-2 scales are one of the most used instruments in the scope of motor assessment. The scales were reviewed by Saraiva and Rodrigues[15] and Rebelo et al.[16] for the Portuguese population and allow assessing the performance of fine and global motor skills in children from birth to 71 months.
Initially, These scales contain a set of assumptions, which we will describe: a) the administration of PDMS-2 is individual and the time required to administer it in its entirety is approximately 45' to 60'; b) The examiner must follow the instructions presented and repeat them to the child 3 times in order to provide the opportunity to reach the maximum score in each item; c) The child must start the test in a specific exercise on the scale, according to their age and continue in the sequence until they fail to perform three consecutive items; d) The examiner starts the test on an item in which 75% of children of that age have a positive evaluation; e) Each item is rated on a three-point rating scale (0 = does not perform, 1 = minimal proficiency, 2 = optimal proficiency).
The results of the PDMS-2 are indicated in three domains of motor behavior, the fine motor quotient (FMQ), the global motor quotient (GMQ) and the total motor quotient (TMQ) that results from the previous two. The scale presents the child's global motor profile, as well as the result of the motor subtests that make up the scale[14]. The scale presents the child's global motor profile, as well as the result of the motor subtests that make up the scale[14].
The items are summed in each of the tests and their value is located in the reference table for age, resulting in a standardized value and a percentile value that can be compared between ages. Subsequently, the sum of the standardized values of the grouped tests makes it possible to obtain the TMQ, GMQ and FMQ according to the consultation of an appropriate table. Finally, the standardized values can be converted into a qualitative classification with categories (from “Very Weak” to “Very Good”), shown in Table 1[14].
The scales are standardized for the child population and have a mean value of 10 points (±3) for each test and a mean value of 100 (±15) for the motor quotients[14].
Table 1. The Peabody Developmental Motor Scales—Second Edition (PDMS-2) subtest standard score values with the associated classification/description.
Standard Scores
|
Classification
|
17-20
|
Very Good
|
15-16
|
Good
|
13-14
|
Above Average
|
8-12
|
Average
|
6-7
|
Below Average
|
4-5
|
Weak
|
1-3
|
Very Weak
|
The results of each test can be expressed through 5 types of final scores: raw score; equivalent age score; standard score or Z-score; percentiles and motor quotients. These scores are the most important information associated with the child's performance. Its analysis provides additional information obtained from the test, which together with other knowledge acquired through other sources results in a good diagnosis of the child's problem[14].
To obtain information about the participants, a child characterization form was created, in which information was collected on whether or not they practiced physical activity in the respective institutions.
1.3 Procedures
After approval by the institution for data collection, an informed consent form was sent and the child's characterization form was requested to be completed, which allowed us to select the subjects taking into account the exclusion requirements of the study. All ethical principles, norms and international standards relating to the Declaration of Helsinki and the Convention on Human Rights and Biomedicine were followed, respected and preserved[17]. This project was approved by the Ethics Committee of the institution where the authors carry out their research.
According to Folio and Fewell[15], examiners who use the PDMS-2 as an assessment instrument must: understand the general procedures for administering the test, its rating and interpretation, for which pilot assessments/studies were carried out to adapt to the instruments. Data were collected by a single researcher, specialist in the area of motor development.
The administration of PDMS-2 was individual and applied for approximately 45 to 60 minutes, in a room or in a large space with stairs. The assessment site was previously prepared in order to provide an environment with the least amount of stimuli and distractions possible on the part of the children. The test application time respected the day care routines, meal, bath and sleep times. Assessments, when interrupted, were completed within five days, as established by the authors of the scale[15].
In order to correctly administer the instrument, the following rules were followed: Instructions were repeated to the child 3 times in order to provide the opportunity to reach the maximum score in each item; the child starts the test at a point on the scale established by their age (these points were empirically determined to allow the examiner to start the test on an item that 75% of the children in the normative sample of that age passed) proceeding in the sequence until the test fails of three consecutive items. The score for each item is 0 to 2 (0 does not perform, 1 performs with difficulty, and 2 performs well)[15]. After the evaluation, the sum of each item is calculated until the final result is established, in global, fine and total motor skills (which is the sum of global and fine skills). Subsequently, the value of the sum of the items, in each of the subscales, is located in a reference table for age, where a standardized value is obtained (from 1 to 20), which can be converted into a qualitative classification with seven categories (from “Very Good” to “Very Weak”)[15].
1.4 Statistical analysis
To code the data we used the IBM - SPSS - Statistical Package for the Social Sciences SPSS (v.23.0). In the first analysis, the sample normality was verified by applying the Kolmogorov-Smirnov test. As we obtained a non-normal distribution (p. <0.05) for all variables under study, we used the Mann-Whitney U test for independent samples, which allowed us to assess the differences between groups. The method of inferences based on the magnitude of the effects was also performed, using the following scale (d Cohen): 0-0.2, trivial; 0.21-0.6, low; 0.61-1.2, moderate; 1.21-2.0, high; 2.0, very high[18].