Randomized clinical trials are the most robust source of evidence in clinical medicine. Unfortunately, financial constraints limit the options for conducting these types of studies. In addition, patient selection bias is a well-known drawback, and not all investigations suit a randomized design. Therefore, observational registries constitute another source of evidence, provided their quality is guaranteed. Research groups and the working groups of medical societies undertake many registries. These are good news, reflecting scientific activity. However, methodological quality is essential to provide valuable clinical data and achieve good scientific results in publications. An independent audit that encompasses all or at least some of the data retrieved is the best way to ensure quality. Scientific societies, such as the British Heart Foundation, support the audit of registries.1 Likewise, local research institutes and foundations may support their investigators in monitoring studies. However, such monitoring is usually restricted to randomized controlled trials and may not be possible for some registries. Nevertheless, minimal quality control is indispensable.

Some registries are based on administrative data.2 Unfortunately, diagnostic codes are not uniform among physicians and centers. As a result, the information collected is heterogeneous. However, the heterogeneity of these types of studies is offset by their exhaustivity. All cases, including follow-up, are collected, and there is no physician-related bias.

Self-reported, nonaudited registries are the most common. However, data quality and their independent monitoring remain an important concern in this type of registry. In studies performed in a few centers, usually with a strong research tradition, quality is taken for granted. Notwithstanding the reputation of well-established consortia in large multicenter registries, quality control is a standard we must pursue. Large multicenter registries are frequently published in our journal, Revista Española de Cardiología, reflecting important research collaborations. This is the case of the activity registries of the Associations and Sections of the Spanish Society of Cardiology, which are highly appreciated by the readership of our journal.3–7 These registries achieve a good balance between a pragmatic design and their objectives. Apart from these exceptions, self-reported multicenter registries should be under some control. The ideal system would be an audit, although we are aware this is not always possible. However, minimum requirements are mandatory. The STROBE protocol establishes the checklist for cohort registries.8 Among the items we consider worth highlighting are the following:

• 1.

  Eligibility criteria and the sources and methods used to select participants

• 2.

  Indicate data sources

• 3.

  Period of recruitment

• 4.

  Report numbers of individuals at each stage of study (eg, numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analyzed). Give reasons for nonparticipation at each stage. Consider the use of a flow diagram

• 5.

  Indicate the number of participants with missing data for each variable of interest

• 6.

  Indicate the number of losses to follow-up

Revista Española de Cardiología will positively appreciate completing STROBE's form8 in articles on self-reported, nonaudited, multicenter registries. Moreover, if possible, our journal encourages the auditing of data (at least some of the data selected randomly). Furthermore, we believe all participating centers should explicitly take responsibility for the data gathered and, as such, from now onwards, articles published in Revista Española de Cardiología will have to include the participating centers and the principal investigator of each center responsible for the accuracy of the data. The aim is to raise awareness of the importance of data accuracy.