Effectiveness Of Complex Interventions Research Articles

Locomotor disability: Meaning, causes and effects of interventions

This paper provides a synopsis of a long-term programme of MRC-funded work on locomotor disability in older people. Specifically it describes the meaning and experience of disability, examines the risk factors for disability and systematically reviews the evidence from randomized trials of complex interventions for disability. We undertook a national prospective study of a representative sample of 999 people aged 65 years or more plus in-depth interviews with a small subsample and a selected sample obtained from hospital sources. Secondary analysis of several large prospective studies was carried out and a systematic review and meta-analysis of published randomized controlled trials of the effects of complex interventions for disability. Very few participants subscribed to the constructs of longstanding illness, disability or infirmity that surveys often use. A wide range of social and psychological factors, independently of chronic diseases, were strongly associated with disability. People with greater functional reserve capacity and those with greater self-efficacy were generally less likely to suffer from catastrophic decline in ability and had better quality of life in the face of disability. In reviewing 89 trials (over 97,000 participants) of complex interventions for disability, evidence of benefits was found although no relationship with intensity of intervention was apparent. Our findings on the meaning and experience of disability suggest the need for modifications to routinely used survey questions and for different ways of understanding the need for and receipt of care among older people with disabilities. The diverse risk factors for disability suggest that novel approaches across social, psychological as well as more traditional rehabilitation and behavioural risk factor modification would be worth exploring. Complex interventions appeared to help older people to live independently and limit functional decline irrespective of age and health status.

Fortuitous Phenomena: On Complexity, Pragmatic Randomised Controlled Trials, and Knowledge for Evidence‐Based Practice

Many of the interventions that nurses develop and implement are in themselves complex and have to operate in situations of irreducible complexity and uncertainty. This article argues that the primary means of generating knowledge for the evidence-based deployment of complex interventions should be the pragmatic randomised controlled trial. Randomised controlled trials represent the only research design to adequately deal with that which we know and (far more importantly) that which we do not. Using the example of practice development as an exemplar for complexity, and drawing on the objections often voiced as a response to calls to make use of randomised controlled trials in nursing and nursing research, the article presents a developmental framework and some methodological solutions to problems often encountered. Randomised controlled trials, whilst undoubtedly methodologically and strategically challenging, offer the most robust basis for developing primary research knowledge on the effects of complex interventions in nursing and their active components.