Quality is a relevant criterion for businesses to achieve customer requirements, but outcomes are not regularly measured using statistical techniques. Furthermore, this knowledge gap makes it difficult for people or technology to control the process, generating increments of hidden poor-quality costs and affecting revenue that should be less than 30% of sales. The article aims to present the results of the Process Capability Analysis on the fulfilment and sample’s turnaround time in a laboratory of a Colombian hospital based on the Lean Six Sigma approach, including statistical techniques that support the decision-making process on wastes in processes, as is the sigma level calculation. The case is a Colombian hospital whose laboratory requires a reduction of the sample’s turnaround time as the primary indicator of service delivery, and we focused the analysis on the administrative and operative criterion. The Process Capability Analysis aims to identify areas for improvement enhancing the efficiency of the laboratory's operations according to its performance or meeting the specifications. We present the results in two ways based on the DMAIC cycle. On the one hand, the process does not have regular time control and traceability, which are administrative criteria that should be adjusted using technology in the short term. On the other hand, we measured the process capability, which is 3-sigma, understood as regular performance in the industry. Further studies should be oriented toward implementing the improvements, measuring the impact of those actions, and calculating savings.