Teacher’s notes
Joint injuries: sampling and statistics
Rationale
Joints can be damaged in a variety of ways. To determine whether some
injuries are more common than others, a large sample must be surveyed
to gather enough data for patterns to be identified.
Activity
Curriculum level 5-6
Living world Topic
Sports studies
Type of investigation
Pattern seeking
Source: Hipkins, Rosemary & Connor, Lindsay. (1999). Alive & well
– A systems approach. Auckland: Pearson Education New Zealand Limited
(ISBN 0 582 86195 0.)
What you need
- Sample of physiotherapist’s appointment book for one morning’s
work.
Note: Supporting activity resources are provided
below.
Focus
- Imagine you have been asked to work out what a typical day’s
work for a physiotherapist looks like. Where would you start?
- What sorts of injuries and conditions do physiotherapists treat?
- Are sports physiotherapists more likely than others to treat joint
injuries rather than other conditions?
- What do you need to know about the way physiotherapists work in order
to know who to sample?
- How many physiotherapists would you need to talk to before you could
begin to make any sort of general statement about this?
Exploration
- In groups, get students to use the information on the table to answer
the questions that follow:
- Create a tally chart to record the numbers of each type of injury
treated during the morning.
- Which injuries are most common?
- In your group, discuss how likely it is that the injuries treated
were caused by sporting mishaps.
- What else would you need to know before you could actually decide
this?
- What other knowledge did you use when discussing this?
- Discuss how many times you think you would need to count samples before
you could begin to answer each of the questions below.
- Is this a typical Monday morning?
- Would a typical Friday morning look the same?
- Would a summer morning look the same as a winter one?
- Get the students to practise their sampling strategies by designing
and carrying out an injury survey of their own,
and justifying why they think their sample is representative:
- What types of fractures are most common in school age students?
- Are ankle sprains more frequent when the netball courts are wet?
Extension
- Different treatments are there for the same type of joint injury.
What treatments other than physiotherapy could be used on an ankle sprain?
How would you test to see if a certain treatment is more likely to be
successful than other treatments?
Reflection
- Why do scientists take samples instead of counting everything?
- How can scientists tell when they have done enough sampling to give
an adequate picture?
- What sort of things did you need to know about a particular kind of
sports injury before you could decide on a sampling strategy?
- What steps did you take to design a sampling strategy that answered
your question adequately?
- What statement can you make about the injury that you investigated?
- How would you convince other people that your statement is true?