Matched pairs design

• This is where you pair your participants up on a certain quality (e.g. putting people with similar intelligence or age together) that is believed to affect the performance on the DV. Each person from the pair does one condition and results are compared to their partners in the other condition
• (+) Reduces participant variables as participants matched on certain characteristics that could affect the DV.
• (+) Reduces demand characteristics because the participants only take part in one experimental condition so are therefore less likely to guess the aim of the study.
• (+) No order effects because participants are only tested once.
• (-) More participants are needed to take part in the study as they each take part in only one condition. Additionally, the researcher probably has to start with a large group of participants to ensure they can obtain matched pairs on key variables.
• (-) Matching participants on the relevant variables can be difficult and time-consuming – how do you match two people on memory or intelligence? It might also be that the researcher thinks they have matched participants on all key variables and then realise later that other variables could have also been important to match the participants on.
• Dealing with the limitations of a

  matched pairs design

  Restrict the number of variables to match on to make it

  easier

  Conduct a pilot study to consider key variables that might be important when matching