using variables to create data object in Javascript

I have this code snippet

      splitTopic = splitTopic.slice(1, splitTopic.length);
      let rawData = data.toString("utf8")
      let correctData = !isNaN(rawData) ? (parseFloat(rawData) % 1 === 0 ? parseInt(rawData) : parseFloat(rawData)) : rawData;
      let datapoint = splitTopic[3]
      let parsedData = { dataPoint: correctData }

What is the correct way of referencing dataPoint to create my data object parsedData.

I tried:

let parseData = {splitTopic[3]: correctData}

But it doesn't like this also