Plan 

This stage involves planning the change that will be implemented and how that change will be monitored for its success. It needs to be clear what is predicted to happen as a result of the change so that relevant data can be collected.  

During this stage, decisions are made regarding what data to collect and the practicalities of data collection such as when, where, how and by whom data will be collected. During the first PDSA cycle, it may be decided that data will be collected without implementing a change so that there is a baseline to compare to once improvements are made. 

Do 

Once plans have been made, the ‘do’ stage should commence on the date agreed during planning. It is important that all of the team are aware of the change and that those who need to gather data are trained to do this in a standardised way. Alongside standardised data collection, less formal information about the problems that the team encounters can be gathered. Any general observations are also useful. 

There can often be unintended consequences of changes, both positive and negative, which should be explored in the study stage. If a change clearly has consequences that could lead to harm, the cycle should be stopped immediately. 

Study 

This stage allows for analysis of the data that has been collected, which can then be compared to the predictions that were made during the planning stage. The data from both before and after the change should be compared. Questions like ‘was there an improvement in the accuracy of discharge prescriptions?’ or ‘did the number of labelling errors decrease?’ should be asked. It is important to reflect on any problems that were encountered and observations that were made. This learning should then be summarised in preparation for the final stage of the cycle. 

Act 

Planning to go onto the next cycle or deciding whether the change can be implemented happens during this final stage. If the change was unsuccessful or had limited success, there may be insights as to why and adaptations made prior to another cycle. It may be the change was a success, but it needs to be spread and scaled up as part of another cycle. Alternatively, the change may have been unsuccessful or had unintended negative consequences and the cycle and change are halted. At this stage, enough might be known about the change in order to adopt it. The key to this stage is acting on what has been learned as a consequence of this cycle.