Documentation is an important mechanism for disseminating software architecture knowledge. Software project teams can employ vastly different formats for documenting software architecture, from unstructured narratives to standardized documents. We explored to what extent this documentation format may matter to newcomers joining a software project and attempting to understand its architecture. We conducted a controlled questionnaire-based study wherein we asked 65 participants to answer software architecture understanding questions using one of two randomly-assigned documentation formats: narrative essays, and structured documents. We analyzed the factors associated with answer quality using a Bayesian ordered categorical regression and observed no significant association between the format of architecture documentation and performance on architecture understanding tasks. Instead, prior exposure to the source code of the system was the dominant factor associated with answer quality. We also observed that answers to questions that require applying and creating activities were statistically significantly associated with the use of the system's source code to answer the question, whereas the document format or level of familiarity with the system were not. Subjective sentiment about the documentation format was comparable: Although more participants agreed that the structured document was easier to navigate and use for writing code, this relation was not statistically significant. We conclude that, in the limited experimental context studied, our results contradict the hypothesis that the format of architectural documentation matters. We surface two more important factors related to effective use of software architecture documentation: prior familiarity with the source code, and the type of architectural information sought.

翻译：文档是传播软件架构知识的重要机制。软件项目团队可采用从非结构化叙述到标准化文档等截然不同的格式来记录软件架构。我们探究了文档格式对新加入软件项目并试图理解其架构的成员可能产生的影响程度。我们开展了一项基于问卷的对照研究，要求65名参与者通过随机分配的两种文档格式之一（叙事性文章或结构化文档）回答软件架构理解问题。我们采用贝叶斯有序分类回归分析了与答案质量相关的因素，发现架构文档格式与架构理解任务表现之间无显著关联。相反，系统源代码的先前接触经验是影响答案质量的主导因素。我们还观察到，需要应用和创造活动的题目答案与使用系统源代码作答存在统计显著性关联，而文档格式或对系统的熟悉程度则无此关联。参与者对文档格式的主观感受具有可比性：尽管更多参与者认为结构化文档更易于导航且有助于编写代码，但这种关系在统计上并不显著。我们得出结论：在所研究的有限实验环境下，我们的结果否定了架构文档格式具有重要性的假设。我们提出了两个与有效使用软件架构文档相关的更关键因素：对源代码的先前熟悉程度以及所需架构信息的类型。