Personal Investigation 2

Question 1

Operationalised variables being assessed

Answer 1

IV: Age- adolescent/young adult(16-24) and adult(25+)
DV: sleep - score on Pittsburgh Quality of Sleep index

Question 2

State an operationalised alternative hypothesis

Answer 2

There will be an increase in the score on the PSQI in adolescent participants aged 16-24 compared to adult participants aged 25+ (higher score=worse sleep quality)

Question 3

Is alternative hypothesis directional or non directional

Answer 3

Directional

Question 4

Justify/Explain why you chose to use a directional hypothesis or non hypothesis

Answer 4

Research clearly states that adolescents and young adults need more sleep than adults. And, due to the phase delay in sleep patterns of adolescents which is mismatched with the school/work, adolescents sleep patterns don’t match their circadian rhythms leading to poor sleep quality.

Therefore, our hypothesis is directional based on this research as we would expect adolescents to have higher scores on the Pittsburgh quality of sleep index compared to adults.

Question 5

Null hypothesis

Answer 5

There will be no significant difference in the score on the PQSI in adolescent participants aged 16-24 compared to adult participants aged 25+. any difference will be due to chance

Question 6

Experimental design

Answer 6

independant groups
due to iv naturally occurring and so IG design most suitable

Question 7

Identify the main characteristics of your sample group and hypothesis and make a link to your variables.

Answer 7

Gathered 21 participants
collected 11 25+ participants
collected 10 participants aged 16-24
All from East Midlands

Question 8

Identify sampling method used

Answer 8

Opportunity sampling
Recruit those people who are most convenient or most available
For example students at college/ family and friends etc who are approached and asked to participate in a study on age and sleep.

Question 9

Explain 2 advantages of choice of sampling technique linking to variables

Answer 9

-More convenient technique than others e.g. stratified because you are able to ask anyone who you come across. When recruiting students it is convenient to ask people in a lunch hall rather than use a sampling frame
-As the P is being approached by us, there are less issues surrounding consent compared to methods such as random, where the P is selected then could say no when being approached by researcher, instead with opportunity sampling you’re able to ask a different nearby adolescent or adult

Question 10

Explain two limitations of sampling technique- linked to variables

Answer 10

-Just because people are available does not mean they are able to take part, not everyone in the lunch hall may feel comfortable taking part in the study.
-Inevitably biased because the sample is drawn from a small part of the population. Only people from the East Midlands are being asked.

Question 11

Step 1 of procedures

Answer 11

Firstly I will approach students at Bilborough College in the canteen and study areas and ask if they are willing to participate in the study.
For the adult sample I will approach staff at Bilborough college or adults around my local area of Nottingham.
First I will ask if they are 16-24 or 25+ to ensure they are suitable to take part in the study.

Question 12

Step 2 procedures

Answer 12

I will then give the students, teachers/adults from Nottingham a briefing statement that outlines the study on age and sleep quality, giving details of the sleep quality questionnaire they will have to complete.
If the p is happy with the information in the briefing statement they will sign the consent form, where they’ll also fill a tick box asking what age bracket they fall under.

Question 13

Step 3 Procedures

Answer 13

Following this I will share the link with the p giving them a QR code to scan for the PSQI and ask them to fill this in on their phone.
After completion, the participant will share their global PSQI score.
We will record the PSQI score and their age bracket in our record table.

Question 14

Step 4 procedures

Answer 14

Lastly, I will give the students, teachers? adults from Nottingham the debriefing statement outlining the hypotheses and purpose of the study and give them the chance to ask questions or withdraw their data.
if they are then happy with the debrief, they will sign to finish the study.

Question 15

identify aan approprite descriptive statistic that could be used to describe the data

Answer 15

mean and standard deviation

Question 16

Explain why your choice of descriptive statistic is appropriate with link to variables.

Answer 16

The mean is appropriate for my data as the DV is measured as ‘score on the PSQI’. This is a score from 0-21, this is a set scale with a true zero an therefore the data is ratio, making the mean the most appropriate measure of central tendency.

As we are able to calculate mean score on PSQi for adults and adolescents, this means that the most appropriate measure of dispersion is standard deviation, as the mean is required as part of the calculation, and gives a more accurate spread of data compared to range.

Question 17

Identify an appropriate graphical representation that could be used to describe the data collected with a link to your variables.

Answer 17

Bar Chart

Question 18

Explain why your choice of graphical representation is appropriate

Answer 18

The graph is displaying the mean scores on he PSQi of adolescents and adults. This data is discrete and therefore a bar chart is the most appropriate way to display the data.

Question 19

Identify an appropriate inferential statistic used to display data collected

Answer 19

Mann-Whitney U-test

Question 20

Explain why your choice of inferential statistic is appropriate and fully link the explanation to your variables.

Answer 20

Mann-Whitney U-test is the appropriate stats test for my data as the experiment is looking for the difference in scores on PSQI for adolescents compared to adults.
The experimental design is independent groups as the participants only complete the PSQI once and as the IV is age, the ps can only belong in one condition (adult or adolescent).
The level of measurement of the data is at least ordinal as the DV is measured as the score on the PSQI which is a score from 0-21

Question 21

Briefly summarise your findings. Descriptive statistics, graphical representation and inferential.

Answer 21

Mean- adults= 5.73 adolescents=8.30

SD- adults=3.36 adolescents=5.00

bar chart
observed value=38.5
critical value=31

Question 22

Conclusions

Answer 22

As the calculated value was 38.5 which is higher than the critical value of 31, the findings were not significant at p=0.05, therefore the null hypothesis was accepted.
This means any difference was due to chance.

Question 23

Identify 2 issues of reliability and how you dealt with them

Answer 23

-During the pilot we did not conduct the research together as a group. This means that the way in which. we delivered the instructions to each group of ps (16-24 and 25+) may not have been consistent between each researcher. This would affect reliability of study. DEAL WITH: we created a set of standardised instructions on how the PSQI was to be completed. Allowing the researchers in our group to give same instructions to each p, increasing internal reliability.

-Due to time restraints we were not able to replicate our research on age ns sleep quality-eating we did not assess the external reliability of study. DEAL WITH: to deal with this issue we would do the test-retest method. after leaving a time gap of a week we would approach the same ps(16-24 and 25+) and ask them to repeat the PSQI. we would then compare the scores on the PSQI from the original data to the new scores a week later. If scores consistent we would have a good test-retest reliability.

Question 24

Explain how you established your research was reliable

Answer 24

We established that our research was reliable through clear operationalisation of IV/DV
IV: age 16-24 or 25+ (adolescents and adults)
DV: sleep-sleep quality measured through PSQI

Another way to establish the reliability of our research is using the split half method. We would split the answers in the PSQI in half (odd qs vs even qs) and compare the scores on each half. If the scores are consistent, then the internal reliability of the questionnaire in measuring sleep quality is high

Question 25

Identify at least two issues of validity you faced in your research, link to variables

Answer 25

-During our pilot study, we saw that participants were being distracted by other people present as they were discussing their answers for PSQI, noisy canteen environments. We also noticed that the people we asked to complete the later in the day were less focussed on completing the PSQI accurately. These are extraneous variables that would affect internal validity of results. DEAL WITH: we asked each participant to complete PSQI only in our presence to avoid distraction of others. We took each participant to a quiet area and asked them to complete around midday to ensure peak concentration, increasing internal validity of results -The questions on the PSQI might have been invasive. The ps (16-24 and 25+) may have wanted to answer questions in a certain way if embarrassed -social desirability bias. So may not have answered a questions accurately affecting internal validity of results. DEAL WITH: only asked for the ‘global score’ as to not invade their privacy and only receive relevant info

Question 26

Identify two ethical issues that concerned you before your research linked to variables

Answer 26

-As the study is on age and sleep, Bilborough College students, teachers and adults from Nottingham may feel it an invasion of privacy to ask them for their exact age and certain questions on the PSQI are quite personal. This can cause for embarrassment for some people. -Before the study began we were concerned about the protection from harm that the Bilborough college students, teachers and adults from Nottingham would receive. The information collected by PSQI could indicate a health issue that they may have or may arise from their sleep quality.

Question 27

Explain what you did to deal with ethical issues

Answer 27

-In order to deal with the potential issue of privacy, we created age categories of 16-24 and 25+ which meant we didn’t ask for the Bilborough students, teachers or adults from Nottingham,information that they might not want to provide. Furthermore we only collected the persons score on the PSQI rather than data from individual questions. -To ensure Bilborough students, teachers and adults from Nottingham were protected from harm during and after the study we gave them a brief telling them that the PSQI may indicate a bad sleep quality score or a potential health problem, so at the end of the study we provided them with links to support them if this was the case and also did a debrief to share the hypothesis and aims of the study.

Question 28

Explain how you established your research was valid

Answer 28

Content validity – ask a sleep expert if the PSQI is an accurate measure of sleep quality. If they agree, then the research has good content validity Operationalisation – clear operationalisation of age (16-24 and 25+) and sleep (sleep quality measured on PSQI) – increases internal validity of our research Concurrent validity – compare scores on the PSQI to another established sleep quality measure. If both measures give the same results regarding sleep quality, our research could be said to have good concurrent validity

Question 29

Explain two ways in which you could improve your research and why these amendments would improve your research

Answer 29

-More varied/diverse sample of 16-24 and 25+ as they were all gathered from a small area of the East Midlands. I would do this by conducting the study online, as this would allow me to reach a wider and more diverse sample of P’s. This would increase the population validity of the study, giving me a more representative result of the effect of age and on sleep quality. -I would improve the measure of sleep that we chose to use. The PSQI is a questionnaire designed to measure sleep quality, but some of the questions were difficult to answer accurately ‘Over the past month how many times have you woken from sleep to use the toilet’ To improve this, I would measure sleep quality through a sleep lab, where a sleep engineer would be able to accurately measure using EEG scans the depth and quality of sleep each P (16-24,25+)is getting. This would improve the internal validity of my study, as the measure of sleep quality is more accurate.