Sources, Data and Quotes: How to Make an Advertorial Credible

Why sources and data matter in sponsored articles

Many readers can tell that a text is sponsored, even when it is not labelled in capital letters. What they are really asking, often without noticing, is whether they can trust what they are reading. Sources and data in articles are how you answer that question. A sentence that says “according to” and names a verifiable origin earns more trust than ten sentences of enthusiasm.

Editors reason the same way. A text that is full of unsupported claims reads as advertising, and an editor who cannot check a statement has a good reason to refuse it. Our publishing rules list unproven claims such as “number one” and “best in Romania” among the forms we reject, for exactly this reason.

This article is about the practical side of credibility: choosing sources, attributing data, handling quotes, linking out and keeping facts current. It is written for marketers and writers who produce advertorials, including those who write for Romanian publications as a foreign brand. If you also want help with the structure and the writing, our SEO article writing service covers it.

Which sources to use

Not all sources are equal. The closer you are to where the information was created, the safer you are. The table gives a rough order.

For Romanian topics, the National Institute of Statistics publishes official national figures, and Eurostat does so for the EU. Romanian legislation is available on the official portal at legislatie.just.ro. If you are quoting a rule, do not paraphrase it from memory. Check the current text, because laws change, and say “as of” a date.

Use the same discipline for claims about search engines. When you write about how Google works, rely on its published documentation, such as its guidance on helpful content, and not on a forum post.

How to attribute data so a reader can check it

A good attribution answers three questions: who says so, when and about what. Compare the two versions below.

Weak: “More and more Romanians shop online.”

Stronger: “According to [named institution], [specific figure] for [specific period].”

The second version is only as good as the figures you place in it, so verify them. Do not copy a number from a blog that does not name its own source. Trace it back, and if you cannot trace it, leave it out.

Rules of thumb for numbers

• Give the date. “In 2025” or “as of June” turns a vague statement into a checkable one.
• Say what was measured. A figure for turnover is not a figure for profit, and a survey sample is not the whole market.
• Keep the comparison fair. Compare like with like, over the same period.
• Do not over-round. Rounding is fine; rounding that changes the message is not.
• Distinguish fact from estimate. If something is your estimate, write “we estimate”, and say on what basis.

Using your own company’s data

Your own numbers are often the most interesting thing you can offer: the number of projects completed, the number of enquiries by type, the average time a process takes. They are also easy to misuse. A few safeguards help.

1. Label them. “In our own records for 2025” makes clear that this is not an industry average.
2. Keep the working. If an editor asks how you counted, you should be able to show a spreadsheet or a report.
3. Resist the flattering selection. Choosing only the best month turns data into advertising. Show the full period.
4. Do not turn a sample into a law. “Of the 40 customers we asked” is not “most customers”.

The same applies to our own site. We state, for instance, that we have published more than 14,000 articles since 2018 and that the portfolio contains 450 sites, and we show where the metrics come from: the public metrics on the portfolio come from PrePostSEO and carry an update date. That level of openness is what a reader can reasonably expect from any company.

Quotes and expert voices

A quote adds a human voice and breaks up the text, but it brings obligations.

• Only real people. A quote must come from a person who said it or approved it. Inventing a “Dr. Popescu from a leading institute” is fabrication and will, rightly, be rejected.
• Get approval. Send the final wording to the person and keep their written approval. A saved email or chat message is enough as a record.
• Use their actual position. Describe the person’s role accurately, and say if they work for the company that sponsors the text.
• Quote others briefly. If you quote from a published source, keep it short, attribute it and link it, instead of reproducing long passages.
• Do not generate quotes. Text produced by a writing tool and attributed to a person who never said it is the same as an invented quote.

Customer testimonials follow the same logic. They need a real customer, that customer’s consent and the actual words. Invented reviews are among the forms we refuse outright. For stories about people and companies, our article on brand storytelling in advertorials shows how to build a narrative from verifiable facts.

Linking to sources

When a reliable public source exists, link to it. A link allows the reader to verify the claim, and it shows that the text is more than a vehicle for a commercial link. Pick the official page, not an aggregator, and check that it opens. Keep the number proportionate: one to three sources in a normal article is plenty, and each should support a specific claim.

This also affects how the article looks as a whole. A text whose only outbound link is a commercial one looks different from a text that cites authorities and then points to your page where it is useful. Neither is forbidden, but an editor will notice the difference. If you want to understand why link patterns across many publications matter, see the article on a risky backlink profile.

Before and after: a hypothetical paragraph

Here is an invented paragraph from a fictional solar installer, followed by a more credible rewrite. The figures are placeholders for illustration, not real data.

Before: “Solar panels are the smartest investment of the decade. Studies prove that every home saves a fortune, and our customers are delighted. We are the number one choice in the region.”

This paragraph contains four problems: an unprovable superlative, an unnamed “study”, an absolute claim (“every home”) and an unsupported ranking. An editor would stop at the first sentence.

After: “Whether panels pay back depends on the roof, the orientation and the household’s consumption. In our own installation records for 2025, the 30 homes we surveyed after the first full year reported different savings, and we explain how we calculated them below. For the current rules on connecting small producers to the grid, check the text of the relevant legislation on the official portal before you decide.”

The rewrite is less exciting at first glance, but it is more useful and it can be defended. It acknowledges that the outcome depends on circumstances, labels the company’s own data, names the period and the sample, and sends the reader to an official source for the rules. It also leaves room for the installer to describe its service in the next paragraph without sounding defensive.

What to do when you have no data

Sometimes there is simply no figure to cite. That is acceptable. A text can rely on explanation, process and experience: how a job is done, which questions customers ask, what typically goes wrong. Describe, do not decorate. If you cannot back a number, write the sentence without it. An article that says less and is accurate is better than one that says more and is wrong.

Keeping data current

An advertorial published on our network remains at the same address, which is good for the link but means the content ages. Prices, rules, opening hours and statistics change. To avoid an out-of-date article:

• write years and dates into figures (“in 2025”), so the reader can judge their age;
• check every number again the day before you send the file;
• avoid time-sensitive claims such as “this year’s new rule” unless you plan to review them;
• keep a log of the sources in a separate document, so that you can update an article later without searching from scratch.

Images need the same care. A chart or photo from another source requires a licence or permission and a named source, which we cover in the article on images for advertorials.

A checklist before you send the text

1. Every figure has a source, a date and a description of what it measures.
2. Every quote comes from a real person who approved it.
3. No statistic is invented, rounded misleadingly or presented as general when it is local.
4. Claims such as “best”, “number one” and “guaranteed” are removed unless they can be proved.
5. Source links are official, working and proportionate.
6. Your own data is labelled as such, and the working is saved.
7. The text still reads as useful if all the commercial links were taken out.

Next step

Take your last draft and highlight every sentence that contains a number or a claim. For each one, write the source beside it. You will probably find a few you cannot support. Those are the sentences likely to make an editor hesitate, and removing them costs you nothing.

If you would rather have someone else write the article, we also offer SEO article writing from the material and sources you provide.

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