Effective speeches use four main types of supporting material: examples (specific or hypothetical instances), statistics (quantified data, interpreted not just cited), testimony (expert or peer opinion), and narratives (stories that illustrate the point). Each type appeals to different cognitive and emotional registers — statistics provide scale, stories provide salience. Oral citation differs from academic citation: sources are verbally identified ('According to a 2023 study published in the Journal of...') rather than footnoted, and their credibility must be established in the spoken attribution, not a reference list. The rule is: every main point should be supported, and every supporting element should be explicitly connected to the point it proves.
Practice oral citation formulas until they sound natural rather than recited. For each piece of evidence, ask: why does this matter? The answer becomes the explicit interpretive link to your argument. Analyze speeches that fail from lack of evidence vs. speeches that bury the argument under unconnected data.
You already know from your work on evidence and support that claims need backing — that assertions without support are just opinions. And from research and citation, you know how to find and attribute sources. In public speaking, those skills apply with a critical twist: your audience cannot stop to verify your sources, re-read a confusing statistic, or look up a citation in a footnote. Everything the evidence does, it must do in real time, in the moment the audience hears it. This is what makes oral evidence use a distinct skill.
The four types of supporting material each do different cognitive and emotional work. Examples — specific instances or hypothetical scenarios — make abstract claims concrete: "Rising healthcare costs aren't just a statistic; consider Maria, a nurse in this county who chose between her mortgage and her insulin." Examples create a face for data, making it memorable and emotionally salient. Statistics provide scale that individual examples cannot: "That story is not an anomaly — 23% of uninsured adults in this state report delaying necessary medication due to cost." But as you know from your research training, statistics need context. "23%" is meaningless without a reference point — compared to what? Better: "23% — up from 9% five years ago, nearly triple the rate." Now the audience can evaluate it.
Testimony borrows credibility from sources the audience already trusts. Expert testimony ("Dr. Chen, who directs the state health department...") works when the audience respects the institution or credentials. Peer testimony ("In a survey of 400 patients just like you...") works when the audience is more moved by relatable experience than by authority. Choosing the right testimony type requires audience analysis — the same expert the speaker finds authoritative may be distrusted by a skeptical audience. Narratives are the most powerful for memorability and empathy: stories are processed as lived experience rather than data, which is why a single well-told story can outlast ten statistics in the audience's memory.
The most important oral evidence skill is the interpretive link — the explicit statement of what the evidence proves and why it matters. In academic writing, a skilled reader infers the connection. In oral communication, you must say it: "This tells us that the problem is getting worse, not stabilizing, which means waiting for a market solution is not an option." Without that link, evidence floats unanchored — the audience has the data but not the argument it's supposed to support. Oral citation is the second key skill: source attribution in a speech is embedded in the sentence, not appended to it. "According to a 2024 analysis by the Kaiser Family Foundation, a nonpartisan health research organization..." The citation must do two things at once: identify the source and establish why that source should be trusted. Credibility is stated, not assumed.