The "preacher's maxim" is an effective formula for writing an argument paper. It says the introduction should tell the reader what you are going to tell them, the body should tell them, and the conclusion should tell them what you told them. In other words, your conclusion should restate your topic and thesis and why they are important. In addition, your conclusion should address opposing viewpoints, explain why readers should align with your position, and present further research opportunities related to your topic.
An APA conclusion should not introduce new points. The key to a convincing conclusion is simplicity, and going beyond the content stated above can muddle your argument and confuse your readers. In general, avoid poetic devices and figurative language. Metaphors, analogies, and rhyming schemes often confuse your meaning, and a conclusion is a place to clearly and concisely state the facts.
It is acceptable to use the first person point of view when writing in APA style. Therefore, you can use phrases like "I studied..." or "We concluded..." when writing your conclusion. First-person pronouns allow for an active voice, which the APA prefers over a passive voice. For example, instead of saying "Interviews were conducted," say "We conducted interviews."
Improper word choice can create misleading sentences. In APA style, certain words are preferred over others. Use "participants" or "respondents" rather than "subjects" to describe individuals that were involved in your research, and use "suggests" or indicates" rather than "proves" to describe the result of your study. Remember, no single study can prove a theory or hypothesis.