practical issues

• Lab experiments


  • Lack mundane realism
  • Have low ecological validity
• Case studies


  • Lack generalisability
  • Collect qualitative data
  • Time consuming (difficult to analyse transcripts and there is no standardised format)
  • Subjective and unscientific
  • Lack of replication
• Artificial tasks

  • Operationalised variables
  • Lack of task validity
• Demand characteristics and experimenter effects


  • Counterbalancing
  • Participant design
  • Randomisation
  • Order effects
• Issues with informed consent e.g. milgram
• Open and closed questions

  Quantitative vs qualitative data
• Interviewing vulnerable people e.g children


  • Have a limited attention span so should be avoided
• Language


  Needs to be appropriate to the group being studied and changed to match age/social class etc
• Topics of a sensitive nature


  • Questionnaires may be better than interviews as more comfortable being honest
• Interviewer

  • Gender and age should be appropriate
  • Some people easier to get on with
  • Accent and appearance can affect the rapport built
  • Ethnicity
• Pilot study


  1. Tests for clarity

  2. Allows the person to be sure that the required information will be gathered
• Setting up questions

  • Avoid creating response bias
  • Avoid negatives
• Postal questionnaires


  • Data may not be valid as we can't be sure that the correct person has actually completed the questionnaire
  • May not be representative of the population being studied
• Deception to prevent demand characteristics e.g milgram
• Animal studies

  • Evolutionary discontinuity (lack generalisability)
  • Humans more likely to show demand characteristics as they are more aware that they are being conditioned
  • Anthropomorphism
  • Lack ecological validity as often in a lab environment e.g. skinner's rats
• Structured observations


  • Lack ecological validity as an artificial environment
  • Lack task validity
• Participant observations


  • e.g working in a mental hospital or joining a cult
• Brain scans

  • Objective measurement
  • Collate and interpret images to create an overall scan image
  • Brain activity is widespread and complex so may not be able to isolate areas of activity responsible for the behaviour
  • Potentially harmful to patients
  • Not generalisable to all
• Twin and adoption studies

  • Issues with allocation of zygoticity
  • Hard to separate environmental and genetic factors
  • Children tend to be placed into adoptive families similar to their biological one e.g race and so the adoptive environment is often very similar
• Qualitative and quantitative data from case studies and interviews

  • Difficult to analyse
  • Conclusions may be unreliable and subjective
• Case studies

  • Lack generalisability
  • Reliability
  • Researcher bias
• Primary and secondary data

  Primary data is expensive to collect as you have to find all the materials and participants etc.
• Longitudinal studies

  • Expensive and time consuming (difficult to replicate)
  • Hard to draw a clear cause and effect relationship as there are many factors changing as time goes on
  • High drop out rates leaving a biased sample which affects validity
  • Clinical psychology is fast developing e.g. drug treatments so by the time a longitudinal study is completed and published the ideas may have already been disproved
• Cross sectional studies

  • Individual differences have a large effect on conclusions
  • Issues with cohort effects
• Cross cultural research

  • May not be suitable to repeat the same procedure in different cultures (different understanding of the procedure and therefore different reactions)
• Meta analysis

  • May be issues with the methods used to gather data
  • Publication bias which may impact upon the validity of the conclusions
  • Research that produces null effects may not be published and so would be ignored in the meta analysis (conclusions would become biased)
  • May include unpublished research but there is increased risk of data not being scrutinised by peer review in the same way