Biopsychosocial Assessment of Cancer Patients: Methods and Suggestions
David M. Dush, Barrie R. Cassileth, Dennis C. Turk in Psychosocial Assessment in Terminal Care, 2014
Direct observation involves having the investigator (or a trained collaborator) record specific response occurrence. Data collection may be performed in either a natural environment (e.g., at home) or in contrived (analogue) situations. For instance, one may have a spouse record the number of times his/her wife/husband dresses a wound postoperatively. Direct observation may be subject to fewer biases than self-report but it is not without disadvantages. Reactivity and observer bias may distort findings. Observers must be carefully trained and reliability checks need to be made in order to ensure accuracy (see Kent & Foster, 1977, for a thorough discussion of this assessment method).
The Measurement of Oxidative Stress in Semen and Use in Assisted Reproduction
Nicolás Garrido, Rocio Rivera in A Practical Guide to Sperm Analysis, 2017
Although the potential value of NBT assay in assessing the differential contribution of spermatozoa and leukocytes to ROS seems promising, several limitations linger. The technique is semiquantitative and prone to observer bias. In addition, NBT can be reduced by many cellular reductases, affecting the identification of a true cellular origin of ROS.33 The varying cellular content of oxidoreductases may also alter the rate of NBT reduction.33 Moreover, the use of the NBT test in clinical laboratories is limited without established normal ranges. Additional studies are needed to define set values on which to base results, to allow for clinical application.
Relevant study design issues
O. Ajetunmobi in Making Sense of Critical Appraisal, 2021
Observer bias occurs whenever subjective factors within an assessor systematically affect the way observations are scored or recorded. For example, a doctor who has a personal preference for ‘Treatment A’ may unconsciously be scoring patients on Treatment A more favourably than patients on ‘Treatment B’ whilst also searching for undesirable side-effects with more vigour with Treatment B subjects than with Treatment A subjects. Such is the human nature.
Supporting trainees in challenging learning environments – is there a way?
Published in Education for Primary Care, 2019
Anna Quine, Charlotte Tulinius
Limitations of the study included not recording the BG sessions and the first author not taking notes during sessions. This was a conscious decision, in order not to inhibit trainee discussion, or take away from the ‘safety’ felt within the group. This resulted in observations being memory-dependent with potential for observer bias. To mitigate this, observations were validated with the facilitators after sessions, and methodology triangulation was used. The groups were an optional addition to training, with trainees volunteering to participate, and groups taking place in the trainees’ own time. This may have resulted in the smaller group sizes due to time constraints, and selection bias. This may have implications for participant uptake and wider distribution of the groups, but the extensive in-depth qualitative evaluation gave very clear and important descriptions of the trainees’ needs and possible gains of participation in a Balint group, even though it was a very short and limited period of study. Further study is required, with a larger sample size and for a longer study period than the pilot allowed.
Effect of eye closure on speech recognition in noise: in light and in darkness
Published in International Journal of Audiology, 2021
E-Ching Eugena Kok, Bradley McPherson
This study had several limitations. First, the experimenter undertaking data collection (the first author) in this study was not blinded to the conditions nor the hypotheses. This could possibly lead to observer bias. Participants were blinded to the hypotheses but not to the conditions as variables in this study are either visible or require voluntary participant action. The participants might possibly guess the experimental hypotheses and exhibit demand characteristics. Furthermore, this study only evaluated the effect of an external visual stimulus by comparing a sound booth in darkness and in light. However, a sound booth in light only contains a minimal and constant external visual stimulus, which is not very stimulating or distracting. This condition is not representative of the usual daily environment, where listeners are typically exposed to a complex visual environment which involves movements and changes. The greater complexity of the normal visual environment will introduce greater distraction and cognitive load, and may affect SRN performance more significantly. Finally, this study used unfamiliar sentences as test materials, while daily conversations are usually composed of contextual sentences, which would be easier to discriminate than those used in this study. Therefore, the results may not be representative of common daily situations, yet may represent unfamiliar communication situations where an individual will experience the greatest difficulty.
Analgesic treatments in people with dementia - how safe are they? A systematic review
Published in Expert Opinion on Drug Safety, 2019
Ane Erdal, Clive Ballard, Ipsit Vihang Vahia, Bettina Sandgathe Husebo
Because people with dementia have reduced ability to verbally report and describe symptoms, the detection of adverse effects from treatment is more difficult in this population than in elderly people without cognitive impairment. Generally, large-scale observational studies such as cohort studies are considered preferable when aiming to describe the prevalence of adverse drug effects. The current review is however limited to randomized controlled trials for several important reasons. Firstly, no large-scale observational safety studies focusing on people with dementia exist. Furthermore, because most studies that include people with advanced dementia rely on proxy-rated symptoms, the detection of adverse events (AEs) is more difficult in this population. Mild adverse effects may not cause directly observable symptoms, or symptoms may be attributed to comorbid disease. Dementing illness frequently causes behavioral and neurological symptoms in addition to cognitive symptoms, and these may be difficult to distinguish from adverse effects. Reports are also highly prone to observer bias. Having a control group allows comparison with the observed rate of AEs in the intervention group, thus increasing the robustness of the results despite the high risk of bias.
Related Knowledge Centers
- Confirmation Bias
- Framing Effect
- Hawthorne Effect
- Anchoring Effect
- Bandwagon Effect
- Bias Blind Spot
- Halo Effect
- Serial-Position Effect
- Observer-Expectancy Effect