Validity and Reliability in Visual Methods

A comment on Validity and Reliability in Visual Methods

Prosser's book 'Image-based Research' (1998) discusses the usefulness of visual methods in qualitative research. In making a case for Image-based Research, the issue of validity and reliability, which are two common research concepts used to establish the truth behind conducted research, is addressed by necessity.

Golafshani (2003) refers to Cresswell & Miller (2000) who explain that both concepts combined function in order to "eliminate bias and increase the researcher's truthfulness of a proposition about some social phenomenon”. Validity deals with the appropriateness of a research method; the extent to which something is measured or explained according to what was intended at the outset of the research. However in order to conclude validity, the reliability of the data has to be demonstrated. Reliability is a term used to evaluate the extent to which the data considered provides an accurate representation of the subject matter, the extent to which results are consistent over time, and if these results can be reproduced by means of a similar research method.

Thus, both the Validity and Reliability of a research project goes hand in hand with trustworthiness. Image-based Research has been argued to be more subjective and therefore less valid and reliable and more prone to manipulation than 'word-orientated' qualitative research. However, Prosser (1998, pp.97-99) explains that this is certainly not the case, and that in fact both research types are confronted by the same issues. In short, the researcher conducting word based research – which depends on texts, interviews and various kinds of evidence – can look at a subject from various angles and is selective according to the sources he or she uses which can lead to various interpretations and multiple meanings. We also have to trust upon the researcher's and his subject’s truthfulness. Research based on visual methods is therefore as valid and reliable as any other type.

Researchers can overcome these issues by taking a reflexive approach to their interpretations. By recognising that both we as researchers and our visual data are socially constructed, and therefore ruled by ideology (Winston, 1998, p.66; Harper, 1998, p. 29), we can demonstrate reliability issues and potential biased involved to the viewer or reader. Thus, when using a visual research method, like photographs or signs and symbols, validity can be shown by providing "constant justification of your interpretation and a relentless internal evaluation of your motives for interpreting in a particular way" (Cano, n.d.). When discussing Photocontext, Adelman (1998 p.151) defines this as making an informed selection of the data considered. Reflecting on the context in which a photograph is made is a particularly important criterion in ensuring internal validity. However if an image on its own does not provide sufficient meaning and therefore lacks a degree of internal validity, as much contextual detail in the form of other visual data in juxtaposition with text and caption, and in combination with other research methods will ensure that the visual data attains external validity, and this allows the researcher to come to a cultural critique and an understanding of the whole (Adelman, 1998, pp151-3; Harper, 1998, pp.33, 36).

In conclusion, the level of validity and reliability in image-based research can be increased by using multiple visual data, and a multitude of techniques which will ensure a multi-level interpretation of the subject in discussion (Winston, 1998, p.66). This process is also termed 'triangulation' (The British Psychological Society, 2004). However reliability will always be an issue in qualitative research as society is not stable, and as culture evolves over time, so do ideas, customs and relationships.


Bibliography
Adelman, C. (1998) 'Photocontext', in Prosser, J. (ed.) Image-based Research: A sourcebook for qualitative researchers. RoutledgeFarmer, London, pp. 148-162.

Cano, V. (n.d.) 'Study Notes: Validity and Reliability in Qualitative Research', Research Trek [Online]. Available at: http://www.qmu.ac.uk/psych/RTrek/study_notes/web/sn5.htm (Accessed: 19 March 2009).

Golafshani, N. (2003) ‘Understanding Reliability and Validity in Qualitative Research’, The Qualitative Report, 8 (4), pp.597-606 [Online]. Available at: www.nova.edu/ssss/QR/QR8-4/golafshani.pdf (Accessed: 19 March 2009).

Harper, D. (1998) 'An Argument for Visual Sociology', in Prosser, J. (ed.) Image-based Research: A sourcebook for qualitative researchers. RoutledgeFarmer, London, pp.24-42.

Prosser, J. (ed.) (1998) Image-based Research: A sourcebook for qualitative researchers. RoutledgeFarmer, London

The British Psychological Society (2004) 'Validity and Reliability in Qualitative Research', Psychological Testing Centre [Online]. Available at: http://www.psychtesting.org.uk/blog$.cfm/2007/3/24/Validity-and-Reliability-in-Qualitative-Research (Accessed: 15 March 2009).

Winston, B (1998) 'The Camera Never Lies': The Partiality of Photographic Evidence', in Prosser, J. (ed.) Image-based Research: A sourcebook for qualitative researchers. RoutledgeFarmer, London, pp. 60-69.