An Investigation into the effect of gender or having a sibling on knowledge of developmental norms in children

An Investigation into the effect of gender or having a sibling on knowledge of developmental norms in children.

Abstract

In this investigation, the independent variable (IV) was whether the participant was male or female, and if they had any siblings. The dependant variable (DV) was their recorded knowledge of developmental norms in children, measured by their score on a questionnaire asking what age on average each stage occurs at.

Three hypotheses were tested which were all one-tailed:

Females will have a significantly better knowledge of developmental norms than males.
Participants with younger siblings will have a significantly greater knowledge of developmental norms than those with older siblings or non at all.
Participants with siblings will have a significantly better knowledge of developmental norms than those without.

The participants involved were 73 first year psychology students comprising of 12 males and 61 females, 5 of which were an only child and 40 of which had younger siblings. Identical questionnaires were administered to all participants and the information collected was used to test all three hypotheses.

The results gathered supported, in all three instances, the null rather than the experimental hypothesis. Neither females, nor those with any siblings or specifically younger siblings had significantly better knowledge on developmental norms than the other conditions. However, despite not proving statistically significant, the results did show trends in the directions predicted in hypotheses 1 and 2.

Introduction

It is important to study development as without devising developmental ‘norms’ (i.e. a universally accepted ‘normal’ age for a child to be able to complete a particular task) children with developmental disorders such as autism or learning difficulties would not be diagnosed until much later on in life. Additionally it helps put parents’ minds at rest knowing that they’re child is progressing at the correct speed and will be able to identify the further help required if this is not the case. Therefore ways of testing children in order to identify or test these norms must be developed. One way to do this is through intelligence tests, the first of which was created in 1905 by Binet in order to identify children who would benefit from additional education. In 1921 Stern developed the concept of intelligence quotient (IQ) from this idea which is now the most common form of assessment. This created a standardised system to compare both children and adults to the ‘average’ or ‘norm’ for their age group.

Some IQ tests work on two scales, a verbal scale and a performance scale (according to the Wechsler Intelligence Scale for Children). The verbal requires the child to complete tasks of general information, comprehension, arithmetic etc, and the performance requires them to code, match symbols and so on. This means all aspects of development and reasoning can be assessed to identify the problem (if there is one) as accurately as possible.

Therefore a good knowledge of these norms is essential in the rearing of children to ensure early signs of learning difficulties etc are not overlooked. Subsequently, it could ...

This is a preview of the whole essay

Therefore a good knowledge of these norms is essential in the rearing of children to ensure early signs of learning difficulties etc are not overlooked. Subsequently, it could be safe to assume that females will have more of an innate knowledge of these due to a maternal instinct and it will be this that is tested. Additionally being around children in a family environment may also acquaint a person with the norms as they will have seen children growing up. This may be the case with people with brothers and sister, younger or older and so these are also being tested. The hypotheses being tested in this investigation are:

Females will have a significantly better knowledge of developmental norms than males.
Participants with younger siblings will have a significantly greater knowledge of developmental norms than those with older siblings or non at all.
Participants with siblings will have a significantly better knowledge of developmental norms than those without.

The aim of this experiment is to see what factors affect how much the participant knows on the topic of child development, through asking them at what age a child can complete specific tasks in accordance with the norms collected by the means mentioned above.

Method

Participants

There were 73 participants used for this study. There were 12 males and 61 females in reference to hypothesis 1, 5 participants without siblings at all and 68 with siblings in reference to hypothesis 2, and for hypothesis 3 there were 40 participants with younger siblings and 33 without. They were all first year psychology students in Exeter University and were selected by their attendance of a practical class. They were assigned to the conditions by their gender and the presence of siblings as answered on the questionnaire. All questionnaires were included in the results.

Apparatus

The only apparatus used was a questionnaire on the developmental norms of children, comprising of 33 questions such as “When are children able to hop on one leg?”. Questions 1-32 were based on the norms taken from the writings of Griffiths and question 33 was taken from a 1994 monograph by Fenton et al (see references).

A cover sheet was attached to provide standardised instructions on how to answer the questions, what they will be on and how it will be scored to ensure confusion and misunderstandings will not be extraneous variables.

Procedure

The questionnaire was administered to all participants at the same time, and they were given as much time as required to complete it. They were then scored according to whether their answer fell into the age range dictated by the previous research mentioned above. The answers were collated and allocated to one condition of each hypothesis being tested according to the appropriate factor (e.g. if they answered ‘yes’ to having a younger sibling).

Results

Hypothesis 1

Table to Show the Mean Score of Males and Females on a Test on Developmental Norms

Table 1

Graph 1

At first glance it is apparent that the scores seem to follow the direction predicted in hypothesis 1, that is that females on average have scored higher than males on the questionnaire testing their knowledge of developmental norms.

As the data collected from this questionnaire is interval data and the design in an independent groups design, the appropriate statistical test to see if the difference is statistically significant or not is the unrelated T-test (see appendix for calculations).

The critical value for a one-tailed test with a degree of freedom of 71, using a significance level of 0.5 is 1.6666. The number calculated from these results is 1.55 and this number must be higher than the critical value to be significant, and therefore although there is a difference, it is not large enough to ensure it had not occurred simply by chance.

Hypothesis 2

Table to Show the Mean Score of Those with Younger Siblings and Those Without on a Test on Developmental Norms

Table 2

Graph 2

Once again at first glance the results do appear to be consistent with the prediction made by the experimental hypothesis, that those who have younger siblings will know more about developmental norms than those without.

As the experimental design is the same as before, an unrelated T-test will be used to test the significance of this result also (see appendix) The value calculated from these results is 0.737 which does not exceed the critical value of 1.666 making the difference between these two results not significant enough to allow us to accept the experimental hypothesis.

Hypothesis 3

Table to Show the Mean Score of Those with Siblings and Those Without on a Test on Developmental Norms

Table 3

Graph 3

For this hypothesis, from both the graph and the table of means it is evident that the trend was in the opposite direction to that predicted. The group with no siblings performed better than those who did have siblings. Because of this, a statistical test will not be conducted as the hypothesis was one-tailed and therefore does not allow the results to be significant if the trend was in a different direction.

Discussion

The aim of this study was to see if gender or whether having a sibling younger or otherwise had an effect on knowledge of developmental norms.

None of the three experimental hypotheses were proved statistically significant despite previous research suggesting that they would be. In all three instances the group sizes were unequal which could be to blame, as a smaller group is less likely to be representative of the population it is from and makes spotting anomalies or unusual results harder to distinguish. This was especially the case for hypothesis 3 in which the ‘no siblings’ condition consisted of only 5 people. The results collected for this hypothesis were also the ones furthest away from the anticipated outcome (the trend was in the opposite direction to that predicted) which suggests this may have been a factor. This problem was mainly down to the sampling method, as participants were selected on their availability rather than their belonging to the various conditions. To counteract this issue while not entirely sacrificing the speed and ease of opportunity sampling, quota sampling could be used as this would ensure equal group sizes.

The questions on the questionnaire were devised in 1984 which means that they could also be out of date. IQ tests and other similar forms of assessment are regularly revised and re-standardised to account for the changes in society and modern life that result in changes in ‘normal’ intelligence and development. Therefore its is likely norms have changed over the last 11 years and so it is possible that the hypotheses generated unsigificant results because the participants were answering the questions in accordance with the modern speed that children are developing at, not that of 11 years ago.

Additionally, it may be possible the results for hypothesis 2 (with the conditions of having younger siblings or not) to be more significant if the age difference between the participant and their sibling was to be taken into account. This is because if there is only a year between them, for example, it is unlikely that they will have any recollection of their development and so be in the same position as those without younger siblings.

These findings do suggest, however, that it is possible that gender and presence of younger or older siblings does not affect participants’ awareness of the age at which children are able to accomplish certain goals. If this were the case, it would mean that women do not have a more innate understanding of this than men and so it is therefore learnt from the environment. Having said this, if having a younger sibling does not affect their knowledge either, the environment in which it is learnt is not isolated to their own home and their own family members. A suggestion for further research could subsequently be to also ask the participants questions concerning their interaction with children in order to take this factor into consideration.

References

Griffiths, R. (1984). The Abilities of Young Children. High Wycombe: The Test Agency

Slater, A and Bremmer, G. (2003). An introduction to developmental psychology. Blackwell.

Slater & Lewis (2002), Introduction to infant development. Oxford: Oxford University Press

Dumont & Williams. (2001). Wechsler Intelligence Scale for Children. Retrieved November 22nd, 2005, from http://alpha.fdu.edu/psychology/WISC-III%20Descrpition_.htm

Appendix

Statistical testing working for Hypothesis 1